Romulan, or Vulcan? Preference-Driven vs. Process-Driven Design in the Field of Small Arms Ammunition

I'm going somewhere with this, I swear.

If you were designing the next small arms round, how would you do it? What methods would you use to determine its physical characteristics and performance attributes? How would you know what was too large or too small, too powerful or too weak? Perhaps more critically, how do different methods for answering these questions compare to one another? Could some methods be better or worse than others?

In this article, we will make our way down this rabbit hole. Our journey will take us through the design of two different rounds of small arms ammunition: one created by an organic method based on selecting the most desirable characteristics, and another created through a systematic process which determines characteristics procedurally. I call these two methods preference-driven and process-driven design.

Preference-Driven Design

Design that is accomplished via the selection and amalgamation of subjectively preferred characteristics from other previous works.

Process-Driven Design

Design that is accomplished through the construction of a process structure which when fed the required data indicates a solution.

For our examples, let us consider two hypothetical nations both looking to construct a new small arms ammunition paradigm. These two nations have very different cultures, and therefore approach the problem differently. The Romulans are a proud warrior nation, inspired by great deeds to act quickly and decisively. Their scientists and engineers use preference-driven design to create new war materiel for their armies. In contrast, the Vulcans are a cogitating nation, who admire great thoughts and science above all else. Their scientists and engineers consider process-driven design the only method capable of creating the most optimum instruments for waging war.

PREFERENCE-DRIVEN DESIGN: THE ROMULAN EFFORT

The Romulan engineer is given the problem of designing a new round for combat out to 600 meters, and immediately begins brainstorming its final characteristics. He is familiar with all of the previous successful small arms ammunition and he knows that the new round must be light enough to carry in quantity, but it must also be powerful to properly dispatch the enemies of the Romulan nation. After considering previous efforts, he determines that the ideal projectile will be 125 grains in weight and 0.277 inches in diameter. He reasons that there are no projectiles of such a mass that are considered inadequate for killing a man, and the 6.8mm (.0.277″) diameter has been determined to be the smallest acceptable size in several previous studies. Noting that low drag projectiles with hard armor piercing cores and fragmenting jackets give better performance than projectiles of other varieties, the Romulan engineer chooses these characteristics to incorporate into his design. He designs a projectile that conforms to these specifications, resulting in a 125gr .277″ caliber three-piece fragmenting armor piercing low drag projectile:

He knows that any new round must also have a good trajectory and relatively high muzzle velocity to be effective and to allow the Romulan soldier to easily make hits at medium range. However, he also knows that a round that is too powerful will actually be counter-productive as it will prevent the soldier from making hits as quickly as possible. Therefore, the Romulan engineer chooses a medium velocity of 2,750 ft/s, high enough for a good trajectory (especially with the low drag bullet), but low enough to moderate recoil.

The engineer’s work is nearly done. All he needs to do now is determine the size of case needed to propel the chosen bullet at the determined velocity. This is quickly determined by computer calculation, and verified in tests:

The resulting round, which he calls the 6.86x46mm Romulan, is completed and passes into the next phase for final modifications and production engineering prior to adoption by the Romulan Army:

PROCESS-DRIVEN DESIGN: THE VULCAN EFFORT

Meanwhile, a Vulcan engineer has also been tasked with designing a 600 meter small arms round. Like the Romulan engineer, the Vulcan has read all of the same papers and knows in equal detail the history of all the same historical small arms ammunition programs. Unlike his Romulan counterpart, however, he does not immediately begin thinking about what the final round will look like. As a logical Vulcan he feels that one of his prime duties is to avoid allowing his own biases to influence the project. Therefore, the Vulcan begins by thinking about what he has been tasked with and how he could develop a process which would give him the best results with the least interference from his own bias. After some thought, he writes down the following seven-step process in his design notes:

How do we create a process to follow for designing ammunition?

  1. Explicate requirements/create criteria – what do we really need to do?
  2. Select candidate projectile(s).
  3. Scale projectiles to several candidate calibers.
  4. Derive minimum velocities to meet each criterion for each caliber.
  5. Add +250 ft/s to criterion that requires the highest velocity, for each caliber.
  6. Model cases which satisfy velocity requirements at given pressure, etc.
  7. Down-select to final round and caliber based on weight and other disqualifying factors.”

According to this process, the Vulcan engineer’s first step is to create a set of criteria for a 600 meter round, which will help him answer the question “what does a 600 meter round actually need to be capable of?” He knows that at this range, it’s not enough for a projectile to simply hit a target, it needs to be able to kill even through barriers, have a good trajectory, and possess good close-range lethality characteristics. In his notes, he jots down some more detailed requirements:

Baseline Requirements:

– Penetrate 3.5mm mild steel plate at 600m and cause lethal wound

– Good lethality (fragmentation, multiple wound tracks) out to 400m

– Point-blank range no less than 300 meters (no more than 5 inch drop at 300 meters)

– Drop at 600 meters no greater than 100 inches with MPBR zero

– Windage at 600 meters no greater than 50 inches with MPBR zero and 10 mph crosswind

Like the Romulan engineer, the Vulcan engineer recognizes the potential of modern low drag three-piece fragmenting projectiles. For step 2, he therefore selects the same shape and design of bullet as the one used by the Romulan engineer. Using computer aided drafting software, he is able to scale this design to five different calibers, recording their relevant characteristics in his notes:

3. Scale projectiles to candidate calibers.

.204

Total Mass: 3.25 g

Jacket Mass: 0.83 g

Slug Mass: 1.47 g

G7 BC: 0.192

.224

Total Mass: 4.30 g

Jacket Mass: 1.10 g

Slug Mass: 1.95 g

G7 BC: 0.211

.243

Total Mass: 5.49 g

Jacket Mass: 1.40 g

Slug Mass: 2.49 g

G7 BC: 0.229

.264

Total Mass: 7.03 g

Jacket Mass: 1.80 g

Slug Mass: 3.19 g

G7 BC: 0.248

.284

Total Mass: 8.76 g

Jacket Mass: 2.24 g

Slug Mass: 3.97 g

G7 BC: 0.267

With the projectiles in each caliber designed, the Vulcan engineer develops simple formulas to help him determine the muzzle velocities each caliber needs to meet the requirements:

Penetration ~ 200 J * ([bullet diameter in inches] / 0.229)^1.5 + [projectile mass in kilograms] * (80 J / ([slug mass in kilograms]))

Lethality ~ 50 J + [projectile mass in kilograms] * (30 J / ([jacket mass in kilograms] / 6) + [projectile mass in kilograms] * (30 J / [slug mass in kilograms])

He finds that in order to meet the penetration requirement, the calibers need the following striking energies:

.204 – 346 J

.224 – 370 J

.243 – 395 J

.264 – 424 J

.284 – 453 J

The math for the lethality requirement reduces to a simple flat figure of 820 J for every caliber. However, the Vulcan engineer also knows that fragmentation will not occur without a certain striking velocity. His research indicates that a projectile of the chosen design must have a striking velocity of 1,900 ft/s or higher in order to fragment. This means that each projectile needs to have both at least 820 J striking energy and at least 1,900 ft/s striking velocity in order to exhibit the desired fragmentation.

Next, the Vulcan engineer uses a ballistic calculator to determine the minimum muzzle velocities needed to meet each requirement for each caliber:

.204

Penetration: 2,920 ft/s

Lethality (energy): 3,420 ft/s (3,670 ft/s adjusted)

Lethality (frag thresh): 2,880 ft/s

PBR: 2,700 ft/s

Drop: 2,780 ft/s

Drift: 2,780 ft/s

.224

Penetration: 2,570 ft/s

Lethality (energy): 2,940 ft/s (3,190 ft/s adjusted)

Lethality (frag thresh): 2,790 ft/s

PBR: 2,660 ft/s

Drop: 2,710 ft/s

Drift: 2,580 ft/s

.243

Penetration: 2,300 ft/s

Lethality (energy): 2,710 ft/s (2,960 ft/s adjusted)

Lethality (frag thresh): 2,710 ft/s

PBR: 2,630 ft/s

Drop: 2,650 ft/s

Drift: 2,400 ft/s

.264

Penetration: 2,070 ft/s

Lethality (energy): 2,640 ft/s (2,890 ft/s adjusted)

Lethality (frag thresh): 2,640 ft/s

PBR: 2,610 ft/s

Drop: 2,610 ft/s

Drift: 2,250 ft/s

.284

Penetration: 1,830 ft/s

Lethality (energy): 2,590 ft/s (2,840 ft/s adjusted)

Lethality (frag thresh): 2,590 ft/s

PBR: 2,590 ft/s

Drop: 2,570 ft/s

Drift: 2,130 ft/s

From these results, he takes the highest velocity for each caliber, and adds 250 ft/s. This gives him the velocity needed to give all required characteristics throughout the barrel’s life and in all climatic conditions:

Resultant velocities:

.204 – 3,670 ft/s (3,420 ft/s + 250 ft/s)

.224 – 3,190 ft/s (2,940 ft/s + 250 ft/s)

.243 – 2,960 ft/s (2,710 ft/s + 250 ft/s)

.264 – 2,890 ft/s (2,640 ft/s + 250 ft/s)

.284 – 2,840 ft/s (2,590 ft/s + 250 ft/s)

To make his final selection, the Vulcan engineer needs to model cartridge cases for each caliber that will provide the required performance at a given peak pressure in the pressure computer. This is done by iterating performance characteristics and case dimensions until the data for the case models and the pressure computer agree:

.204:

.224:

.243:

.264:

.284:

The Vulcan engineer then records some relevant characteristics in his notebook before making the final down-selection:

.204 Vulcan:

Case mass: 7.70 g
Propellant mass: 2.44 g
Projectile mass: 3.25 g
Primer mass: 0.25 g
Total mass: 13.64 g
Relative capacity: 4.56 in
.224 Vulcan:

Case mass: 6.61 g
Propellant mass: 1.94 g
Projectile mass: 4.30 g
Primer mass: 0.25 g
Total mass: 13.10 g
Relative capacity: 2.99 in
.243 Vulcan:

Case mass: 7.29 g
Propellant mass: 1.98 g
Projectile mass: 5.49 g
Primer mass: 0.25 g
Total mass: 15.01 g
Relative capacity: 2.61 in
.264 Vulcan:

Case mass: 8.44 g
Propellant mass: 2.46 g
Projectile mass: 7.03 g
Primer mass: 0.25 g
Total mass: 18.18 g
Relative capacity: 2.73 in
.284 Vulcan:

Case mass: 10.08 g
Propellant mass: 3.01 g
Projectile mass: 8.76 g
Primer mass: 0.25 g
Total mass: 22.10 g
Relative capacity: 2.90 in

Now, he knows everything he needs to make his final selection. The best round to meet the requirements is the one that is the lightest and smallest of the five, and the one that does not produce any negative characteristics that would impede its suitability as a military caliber, such as excessive barrel wear. Therefore, the Vulcan engineer’s choice is the .224, as it is the lightest without having an excessive relative capacity (over 3.5 in). The .243, .264, and .284 calibers all satisfy the requirements, but they are 15%, 39%, and 69% heavier than the .224. The .204 is comparable to the .224 in weight, but has a relative capacity of 4.56, far in excess of the target 3.5 in, which suggests it would produce excessive barrel wear characteristics.

The Vulcan engineer completes his report, recommending the .224 caliber and its performance characteristics for future exploration. He also notes in his report that if the .224 caliber is for some reason deemed unsuitable for adoption, that the next caliber up – .243 – can be investigated, and so on until a suitable round is reached.

The Vulcan engineer’s candidate rounds, left to right: .204, .224, .243, .264, and .284 caliber.

 

CONCLUSION:

With these examples, we can get an idea of how the two design methods compare. While a more extensive discussion of the methodology of these examples and how the methods compare will follow tomorrow, we can already tell that the preference-driven method is much faster and simpler, but produces less well optimized results. The process-driven methodology is much more involved and takes more time, but it produces better optimization by offloading most of the decision making to a set of engineered processes. As part of this, the Vulcan engineer conducted what I call a “spectrum study“, which is an evaluation of multiple different calibers that all meet the same criteria. By taking each caliber and creating a solution to the problem, he was able to eliminate ones as being either excessively powerful or unsuitable for service in some way, until he reached the optimum according to his criteria. Perhaps most critically, the fact that the conductor of a spectrum study does not know what the final configuration will be helps remove bias from the decision-making process, allowing for a better optimized solution.

Although process-driven design is capable of making better decisions than the preference-driven method, it does have limitations. Most obviously, the optimization will only be as good as the processes that are created to provide it. If the criteria used to select the optimum are faulty, the “optimum” that results will not meet the need it was designed to fill. A round selected according to a process with no more stringent criteria than “penetrate a piece of paper at 10 meters” will likely not meet the needs of a military user, for instance. In this same way, process-driven design may not produce good results if the problem is insufficiently understood, as in that case a sound process may be difficult or impossible to create. More intuitive preference-based methods may in such cases produce better results by virtue of simply not being optimized for the wrong criteria. Also, if the criteria are so stringent and well understood that the possible solution space is extremely narrow, then a process-driven method may be a waste of time, as the correct answer is plainly obvious in that case.

Having said that, the benefits of process-driven design are obvious in these examples. The process-designed optimized “Vulcan” round ostensibly meets the same range goal as its preference-designed “Romulan” round, while being a full 31% lighter (.224 Vulcan is 13.1 grams vs. 19.1 grams for the 6.86mm Romulan), as well as 28% smaller. Since the two rounds are quite different, they cannot be compared in every single respect, but it is notable that in a couple of important respects the .224 Vulcan may actually perform better than the larger 6.86mm Romulan. The .224 Vulcan, for example, has 90-120 meters more range where striking velocity is above 1,900 ft/s, than the 6.86mm, implying a significantly longer fragmentation range. Also, due to its much higher muzzle velocity, the .224 Vulcan can be expected to perform better against body armor, and may exhibit adiabatic shear effects against Level III steel armor out to 120 m or more, where in comparison it is unlikely that the 6.86mm Romulan will exhibit these effects at any range.

Tomorrow, I will publish a “behind the curtain” review of these experiments, which will also include a more in-depth ballistic comparison between the two rounds, as well as further discussion of preference-driven and process-driven design. In the meantime, let us know in the comments section below what you think about these two examples, the methodology presented here, and the potential benefits of either preference-driven or process driven design!





Nathaniel F

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He is also the author of the original web serial Heartblood, which is being updated and edited regularly. He can be reached via email at nathaniel.f@staff.thefirearmblog.com.


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  • John A. Smith

    I wouldn’t. I’d recognize the blindingly obvious: the world is already saturated with well-designed choices, differences between the best are tiny and irrelevant, and that small arms don’t win modern wars.

    • noob

      True indeed. It’s probably the intimate emotional connection people have with small arms because they are relatable on a level and a human scale that say the SM-3 missile in the Aegis Combat System is not.

      Tactical knives and bayonets don’t win wars either but it doesn’t stop people obsessing over them. It is part of being human.

      • Yeah, my criteria for a bayonet are (in order):

        1. Is it a good field knife when it isn’t a bayonet?

        2. Is it sturdy enough to work as a bayonet?

        3. Does it stick out past the rifle at least 7″?

        Everything else is merely “It would be cool if…” And I even include one of *my* favorite attributes of a bayonet as a merely “wouldn’t it be cool if…” – a matte “in the white” finish (you don’t black for covertness, and 90% of a bayonet’s utility is that the other guy can tell you have it mounted – they are PSYCHOLOGICAL weapons more than anything else.)

    • PK

      “small arms don’t win modern wars.”

      Don’t worry, the same sort of obsession over minutiae exists for designing artillery of all kinds, missiles, and so on.

      If the end result is “your enemies die and you don’t”, we (as a species) tend to give it our all.

    • randomswede

      Small arms have never really won wars, unless there’s a technological gap (muskets vs AR-15s) it just decide where and at what distance the fighting will be done.

      • Major Tom

        And then the weapon designed for such arbitrary standards suddenly finds itself faced with reality and it’s out of its league. For example, M14’s in Vietnam. Powerful, accurate but clumsy in the jungle. Then the M16/M4 in Afghanistan. Light, accurate, but frequently and easily outranged in open terrain.

        • randomswede

          It’s almost like a nation that fights all over the globe might need more than one type of round to feed their assault rifles. (As in, pick the big one or the small one and then every one who goes to that theater gets the rifle issued in that round)

          • CommonSense23

            That would only make sense if soldiers could take advantage of the abilites that cartridge is capable of.

          • ostiariusalpha

            It will be a long while before the TrackingPoint and AimLock tech matures to the point that it will be standard issue on service rifles.

          • Major Tom

            Something like that. Trying to force universal ammunition while good and simple for logistics, makes for an awfully square-peg-meets-round-hole combat often giving the wrong tools at the wrong time.

          • or… don’t fight allover the globe… not that the diversity of American terrain would negate the dual option necessity anyways…

        • CommonSense23

          What is the M16/M4 being outraged by. Cause its probably going to our range 7.62 NATO also.

          • Major Tom

            The same things that cause us to drag around heavy as hell 240B’s on patrol, issue refurbished M14’s in a DMR role, adopt the SCAR-H for the Rangers and cause the Interim Combat Service Rifle or whatever it’s called this week to be 7.62 or better.

            That is to say the assorted .30 cal rifles and machine guns that can engage us beyond 600 meters while our 5.56mm weapons are largely ineffective. The PKM, SVD, Lee-Enfield, Mosin-Nagant, ya know stuff of wars past and present that prove the folly of relying on submachinegun range weapons.

            Were Timmy Taliban a better shot and better quality soldier, those tactics would have had us fleeing Afghanistan years ago because of the high casualty rate making for one hell of an anti-war movement.

          • I think they represent the folly of not using combined arms, rather. Why is, in TYOOL 2017, any regular US Army unit engaging people at over half a klick without support?

          • Major Tom

            Because the ROE doesn’t let us and/or we don’t always have assets available. In remote terrain of many places such as Afghanistan, the nearest place you can set up an artillery fire base might be well out of range of the artillery and the enemy dug in in a region that doesn’t allow much vehicle travel.

          • Yeah, so, uh, here’s an idea: Change the ROE?

            Like if the ROE is literally breaking the entire system upon which your force is designed (combined arms), maybe it’s not a good ROE?

          • Major Tom

            But that would mean the brass would have to admit they’re making a mistake and we both know they won’t do that publicly.

            Yes a changed ROE would mitigate or eliminate some of those problems but we’d have a lot more civilian casualties in the process. But unless we wanna go full Dresden and say to hell with civilian casualties, we gotta be mindful of that.

          • Then figure out a way to couch it so they can, instead of joining the lobby that is trying to ram a caliber down the Army’s throat that won’t do anything but further overload the soldier

          • Brett baker

            “Enter now into the city, and do kill everyone and everything within. Spare no one, but do kill every man, every woman, and every child. Spare no thing, but do kill every cow and calf, every horse and foal, every sheep and lamb, every goat and kid. Take nothing for yourself. Any gold and silver you find, give it to the temple. Take nothing for yourself. For I AM WHAT I AM, who is Lord God of Israel, so commands you.” It worked millennia ago, and would work today.

          • noob

            in the very next verse: “But Saul and the army spared Agag and the best of the sheep and cattle, the fat calves and lambs—everything that was good. These they were unwilling to destroy completely, but everything that was despised and weak they totally destroyed.

            Then the word of the Lord came to Samuel: ‘I regret that I have made Saul king, because he has turned away from me and has not carried out my instructions.’ Samuel was angry, and he cried out to the Lord all that night.”

            So no, it didn’t work back then. Very, very few peoples have what it takes to complete a genocide. Any survivors of a genocide will be effectively the products of a Darwinian selection event – The best of the best, the smartest of the smart, the strongest of the strong. By definition the survivors are stronger and swifter than those who tried to kill them. And survivors of genocides tend to be, how shall we say, “unforgiving.”

            No, if you want to destroy a people get them hooked on opiates and alcohol and then feed them high fructose corn syrup and trans fats until they die. It is a surer way than a bullet.

          • noob

            What if: we made full use of the huge American domestic small arms industry by buying well made COTS uppers that converted the AR-pattern lower receiver and user interface to whatever caliber slightly out-ranges the opposition. Say by 10% overmatch. When arriving in country, you are presented with an optics ready upper for your AR-15 pattern or AR-10 pattern rifle, with the reticle on the optics already dialed in for the bullet drop of that cartridge – and it is a reticle that is the same design just with different range marks as all the other calibers. You should be able to take to the manual of arms by muscle memory. You might even forget you are using a different round from your training – that is for the supply clerks to worry about. (The upper also has back up offset iron sights or a micro red dot at your preference, for when a telescopic optic is cumbersome). The ammo issued is specific to that theater of operations. Unless you are in a seriously secret squirrel outfit you aren’t going to be bouncing between central africa, afghanistan and the 9-dash line in the pacific anytime this week so there will be plenty of time to refit you while you are en route.

          • neoritter

            So that’s part of what the whole point was that spawned the SCAR, XM8, ACR, etc. Same gun, easy swap out of parts to allow for different calibers, barrel lengths, etc.

      • noob

        “Arithmetic on the Frontier” by Rudyard Kipling

        A scrimmage in a Border Station —
        A canter down some dark defile —
        Two thousand pounds of education
        Drops to a ten-rupee jezail —
        The Crammer’s boast, the Squadron’s pride,
        Shot like a rabbit in a ride!

        No proposition Euclid wrote,
        No formulae the text-books know,
        Will turn the bullet from your coat,
        Or ward the tulwar’s downward blow
        Strike hard who cares — shoot straight who can —
        The odds are on the cheaper man.”

    • gunsandrockets

      Yes small arms don’t win wars. And artillery has been the king of the battlefield arguably since the Franco-Prussian War of 1870, where the French had the better rifles and the Germans had the better artillery.

      But even if we are talking about modern small arms, I’m amused by the fixation on rifle/pistol/machine-gun calibers or designs. The universe of contemporary infantry weapons is incredibly broader than that, yet those vital weapons never get the attention they deserve.

      I would say the most important small arms development since WWII was the breech loaded 40mm rifled grenade launcher.

      • iksnilol

        PREACH IT, BROTHER!

        AD VICTORIAM, 40MM!!!

        • noob

          FOR THE EMPEROR!

          • James Earl Jones

            Blood for the blood god! Skulls for the skull throne! Wait… I mean the Emperor protects… Yeah… Go Imperium.

          • Willem of Byrgenwerth.

            Fear the old Blood. Our Eyes are yet to open.

          • noob

            behold the coagula

          • noob

            Slaanesh sits upon your face! THE TAINT OF SLAANESH IS UPON YOU!

          • James Earl Jones

            I’m always surprised at how many 40k fans are on here. I always thought we were a pretty small group.

          • noob

            🙂 it’s like a secret handshake.

          • Joby

            Milk for the Khorne Flakes!

      • Brett baker

        Some of us prefer air defense artillery, the drag queen of the battlefield.

        • marathag

          Another Damn Army for the Win

  • noob

    I love this, especially the idea of a spectrum study (if you have the budget for that many iterations). The only thing i don’t get is the step where the Vulcan will “Add +250 ft/s to criterion that requires the highest velocity, for each caliber”.

    Would not the vulcan try increasing the velocity in 5% increments for up to 25% over the minimum velocity to get a spectrum of max velocities? Then you could tune the poweder knowing how much velocity variation was a dealbreaker.

    • Wolfgar

      I think you and Nathaniel have nailed it! NICE.

    • +250 ft/s accounts for the life of the barrel plus climate. In other words, the weapon will still meet the performance requirements when it is nearly shot out (a worn out barrel in the US military is defined as one that shows a velocity loss of 200 ft/s or more) and being fired in cold weather.

      • noob

        Ah! A government requirement plus 50ft/s for the cold. Got it.

        • I don’t think the government actually requires specified performance at a velocity deficit, but they should.

  • Geoff Timm

    Just take all the candidates, toss three examples of each into a large bucket, put the lid on, shake well, have small girl reach in and take one. Make that the standard. Geoff Who figures it will be faster and more cost effective than any system the US Army has devised and will work well enough. I also remember the 5.56 vs 7.62 controversy, that continues relentlessly.

    • noob

      And no matter what we choose people will hate on it.

    • Gregory Markle

      Then politics come into play and a round not even in the bucket is adopted because they took the right guys out to dinner more times.

  • noob

    #goals.

    Colonel Jack O’Neill: This

    [holds up Goa’uld staff]

    Colonel Jack O’Neill: is a weapon of terror. It’s made to intimidate the enemy. This

    [holds up P90]

    Colonel Jack O’Neill: is a weapon of war. It’s made to kill your enemy

    https://uploads.disquscdn.com/images/36db2e3dc9f297d2e6a10ea7b81964177e694dbb1d418430d9ef24ce7362300a.png

    • PK

      I can’t avoid loving any Stargate reference… that show is the real reason behind my getting a PS90 and subsequently registering it as an SBR as fast as I could.

      https://uploads.disquscdn.com/images/3d7aa450dd7a5087a1c59e3ad4d61f5247829efa82917dad0a8bc6ca711cf7d6.jpg

      • randomswede

        What can you realistically get done with only 400 rounds. (That right there is sarcasm)
        I’m guessing the pockets could hold another 400 in boxes, if you haven’t solved the issue by then it’s time to seek some kind of help either way.

        • PK

          Well, you know, that many rounds only goes so far when you’re fighting Goa’uld…

      • Twilight sparkle

        I’m glad I’m not the only one that bought a ps 90 because of that show, haven’t SBRd mine yet

        • PK

          “haven’t SBRd it yet”

          Heresy!

          Honestly the $200 was worth it, every penny, because of how much handier it is while being more enjoyable to shoot. I’ve shot that rifle so much that I’ve had to replace the barrel a few times!

          • Twilight sparkle

            I would have done it awhile ago if I hadn’t decided to go back to school.
            Are you using cmmg barrels?

          • PK

            The first one was a P90 barrel from a stripped SMG, but the others have been CMMG and… there was some small outfit that offered non-chromed barrels for $100 introductory, years ago, and subsequently folded.

            The CMMG barrel is every bit as good as the FN barrel, by the way. My only complaint is that when I’m running a 1/2×28 for a silencer instead of the FH, it does tend to erode badly after a few thousand rounds. I consider it a consumable part, for sure!

          • Anonymoose

            Well, it’s a good thing they make all those affordable .22 suppressors that are 5.7-rated now.

          • PK

            Back in the day, I had to use a 5.56 can… and it still manged to be light and handy.

          • Gun Fu Guru

            “I’ve shot that rifle so much that I’ve had to replace the barrel a few times!”
            How many pesos did that set you back?

          • PK

            It varied, ammo changed price a lot at first, and the barrels were anywhere from $100-400, depending on brand/features. Averaging, I think it was something like thirty cents a shot, over time… and that was with the FN factory match grade ammo only.

            Worth it, in other words. Wholly worth it.

          • Gun Fu Guru

            Only $0.30/shot? Not as bad as I would have imagined. Might have to look at it again.

          • PK

            Well, check out the prices on ammo. It seems to have stabilized on $16-18/box, and that’s for the blue tip FN factory ammo, and it’s 50rd boxes. It’s really not bad, at all.

          • Grant

            What kind of barrel life are you getting?

            I’m also curious about the reliability of the PS90. What I’ve heard hasn’t been great, but I’ve never run across anyone that has really shot one.

            I’ve always thought they were neat and if I hear enough good things I might put one on my buy list.

          • PK

            The barrel life really depends on if I go a bit nuts with rapid fire, or if I’m firing hotter rounds than the blue tip, or if I’m using a silencer… but easily 10,000+. I would have to look at my logbook to make sure, and I don’t have it handy right now, but I was going at least five cases between swapping barrels. What’s great is that not only are the barrels fairly reasonable in price for what you get, but that it’s hardly more difficult than swapping an AR barrel. A pair of wrenches, and a minute or so. The 16.1″ factory barrel, however, is pinned to the shroud and must be cut loose.

            Reliability is outstanding. The only failures I recall were failures caused by using one particular silencer. I don’t believe I experienced any others, and that one problem was intermittent and stopped when I stopped hanging a four pound silencer off the end… it was all I had with me, that day, and I didn’t want to shoot without a can.

            They are neat, and they are nice for what they are. What they are is handy, fairly accurate (depending on which sights you go with or buy installed), and have a so-so trigger. It’s not the dreaded bullpup trigger that is stereotypically 10+ pounds and an inch of grinding takeup, either. The trigger, while still very obviously actuated by a pair of connecting bars, fits in with much more modern bullpup triggers. It was ahead of its time, and at the time the P90 came out, even at the time the PS90 came out, it was likely the best on the market.

            From the moment I handled one I found the PS90 handy, even with the factory 16.1″ barrel, relatively light, and thankfully they’re no longer all that uncommon. Mags can be found easily, ammo is easy enough to order and commonly on sale with free shipping from Palmetto State Armory, and in my mind there are only two drawbacks… the cost of the rifle itself, and the scarcity of factory-direct parts. The rifle, I believe to be worth the cost. The FN parts being unavailable doesn’t seem to be an issue, as I haven’t needed to replace anything but the barrel so far. The FCG is plastic, and yet it’s held up for tens of thousands of rounds!

            Basically, what I’m saying is that they really are nice little rifles and most of the complaints seem to stem from a time when ammo was hard to find, mags were hard to find, and both were expensive. The lack of FN parts isn’t a big deal to me and I’ve given mine a decade of regular use, the trigger isn’t terrible, and I’ve always had a lot of fun with it.

          • Grant

            Thanks for the reply. I’ve still got 4x more Stamps to fund along with some 922R parts. Once I clear my current backlog I will have to think about one of these.

      • noob

        That is one sweet set up! Can you get a plate carrier that holds the mags at a 45 degree angle canted outwards?

        • PK

          Probably! That carrier was made for me years ago, I’m not sure if The Vest Guy is still in business but that’s who produced that vest.

          • noob

            Thanks! I hope the vest guy is still going strong.

    • ActionPhysicalMan

      I like the gun but thought the show was unbearably stupid. I am in no way implying you or others that liked the show are stupid. I suspect that you are just more tolerant of things gratuitous and things that don’t make sense.

      • The show is incredibly stupid for the first few seasons. I think it only gets (relatively) smart around season 5 or 6.

        • Nunya Bidniz

          Funny, that coincides w/ the transition to Fargate and MacGuyver leaving the show. And I thought *I* was the only one who noticed!

          Stargate Atlantis was just a whole lot more fun all around…

          • I liked Richard Dean Anderson as Col. O’Neill, but around the time Ben Browder joined the show the writing staff got changed up and the episodes got substantially better.

            I am gonna disagree on Atlantis. It was OK. The best part about it was the Wraiths, the worst part was probably the cast, especially Sheppard. Rodney McKay came into his own, too.

            But then, I am one of those weirdos who really liked Stargate Universe…

          • PK

            I found one! I finally found someone else who liked SG:U!

          • PK

            Nah, the change away from the original characters didn’t happen until season 9.

          • Oh damn son, you’re right. Clearly I need to re-watch the show…

      • Kelly Jackson

        I find it hard to go back and watch the show today, but at the time it was on the air it wasn’t bad.

      • noob

        I loved how silly the show was. In the clip i mentioned they showed a p90 cut a tree trunk in half as part of a weapons demo. I laughed so hard at that. It represented an escape from my real life world where things are solid and cold and largely underwhelming.

    • Brett

      Did anyone else watch this show/Shows and go “Why is it just a majority of Air Force Officers?”

      • noob

        Yeah! I got the impression that they just lifted the ranks from the US Space Program (not realizing that space vehicle pilots need are officers because they are pilots.) I’d expect a larger number of officers to share the load of making political policy decisions in the Green Berets style “Foreign Internal Defense” missions the Stargate program does but you’d expect also a weapons Sgt and some CIA guys as well. Maybe that’s what Teal’c and Jackson were supposed to be, except in a more family friendly form. And where are the enlisted guys who will be pulling security, being P90 instructors and medics and admin and so on? Is it that every time the Stargate is dialed, they have to use enough electricity to light up the eastern seaboard so they can’t dial very often?

        • Brett

          Yes and :
          1. While I always assumed the team was more of emissary duty. Go to new planet, meet locals (if any), find new artifacts (if any), obtain resources in the fight against/combat encounter with (insert name of baddy here). Where was the security?
          However:

          2. Teal’c with a “M249” and Zat’nik’tel can solve most problems. I still would have liked to see a few more ground pounders in more elevated roles beyond Sgt. “red shirt”.

          3. Merry Christmas, in case I forget in a few months.

          4. And yes, there were many background players and extras the filled those roles Sgt Walter Harriman (later CMSgt). Next to him, the next most prominent enlisted personnel are those 2 generic guards with rifles they keep using the footage of them walking.

          5. While this may be more of a personal gripe and I know it was on a Air Force base, but I would have like to see some Marines, Soldiers, hell I’ll take some Sailors. Joint Task force or something.

          • noob

            Agreed on all points – a salty enlisted marine who would have brought a bit of seasoning to the proceedings.

            As far as inter-service rivalry goes – I get the impression that in the Stargate Universe the Air Force believed in the whole “Alien Gateway to Other Worlds” project when everyone else thought they were crazy, so when the thing actually worked they fought tooth and nail to keep the other branches of the military out and keep all the cool tech to themselves. They’d paid for it in blood and treasure, and they understood it better than anyone, so they were gonna keep it!

            Evidence for this in story is that it took a whole separate federal Department in the form of the Rogue National Intelligence Department Agents headed by the corrupt Senator (later Vice President) Robert Kinsey to make inroads into the Cheyenne Mountain Complex where Stargate Command was basically a kingdom unto themselves. After that failed to crack them open it took the United Nations to apply pressure to create the International Oversight Advisory, and that still didn’t stop the air force basically being in charge day-to-day.

            Since you can’t fit a M1 Abrams though a Stargate, the Stargate Universe Air Force didn’t feel the need to ask anyone else for help. The rewards of a monopoly for half a decade and the power that brought were just too high.

  • Fast Forward

    How about; take:
    a .276 Pederson and a 30-06 which one do you think will win?
    a 7.62×51 and a .280 which one do you think will win?

    • Nicks87

      Dont you talk bad about mah 30 caliber!

      • Fast Forward

        That rootin’- tootin’ .30 is mah Klingon neutralizer.

    • 6.5 Creedmoor and 6.5x47mm are, from the average soldier’s perspective, virtually identical to 7.62 NATO. They are virtually the same mass as 7.62, and only really offer performance benefits beyond the range most guys can shoot.

      Being that 7.62 is already in service, I don’t see the idea of fielding one of the commercial 6.5s as a general caliber as making much sense.

      • randomswede

        What are you even commenting on?

        • …His comment?

          • randomswede

            He never mentions any 6.5 caliber rounds or suggests replacing any round in the present.

          • Does this part not appear for you? “Logical decisions are often; ‘lost in space.’
            Why force the 600m criterion?
            Just adopt 6.5C, or 6.5×47 and spend the saved money on healthcare and education.”

          • randomswede

            “How about; take:
            a .276 Pederson and a 30-06 which one do you think will win?
            a 7.62×51 and a .280 which one do you think will win?”

            Is all that I can see.

          • Twilight sparkle

            Try refreshing your page, I think he edited it. I can see the 6.5 stuff

          • randomswede

            I see it now. I was lured into thinking Disqus updated everything “realtime”.
            Perhaps admins can see the edits before users?

          • Ports

            “Just adopt 6.5C, or 6.5×47 and spend the saved money on healthcare and education.”

      • Fast Forward

        I’m happy……that you are happy with 7.62!

        What was the Article about?

    • gunsandrockets

      .276 Pedersen vs .30-06

      Ah, it all depends on what you want. Short version: I think the U.S. should have used both for WWII.

      No question a .276 Pedersen Garand rifle would have been superior to the .30 caliber M1 rifle. Less weight, more capacity, less recoil, better handling, lower ammunition weight, all in all a boon to the poor bloody infantryman.

      But arguably the most important small arm of the U.S. Army in WWII wasn’t the rifle, it was the machine-gun. And the most important use of the machine-gun during WWII wasn’t ground guns used by infantry, but vehicle mounted machine-guns. And the criteria for what is a good machine-gun for a tank is significantly different from what is the best machine-gun for infantry.

      The 1919 .30 caliber Browning machine-gun, though a mediocre infantry weapon is an excellent tank machine-gun.

      There are very good practical reasons aside from legacy and custom why today, decades after WWII, a .30 caliber machine-gun is the defacto choice for tank co-axial armament and ground vehicle armament around the world.

      • “Short version: I think the U.S. should have used both for WWII.

        No question a .276 Pedersen Garand rifle would have been superior to the .30 caliber M1 rifle. Less weight, more capacity, less recoil, better handling, lower ammunition weight, all in all a boon to the poor bloody infantryman.”

        Naw, I don’t see it. Ammo weight would have been negligibly less. Rifle weight would have been a bit better, but still not dramatic. Capacity would have been the same (.276 T2 had the same base diameter as .30-06). Recoil characteristics would have undoubtedly been better, but the M1 is really soft-shooting anyway. And the M1 already handles like a peach.

        The rounds are just too close together to justify the second one. I realize I’m a party pooper by saying this, but MacArthur had the right of it.

        • politicallyincorrectshooter

          IMO, a better choice might have been Hatcher’s 125 Gr “.256” in a (thicker rimmed?) .250 savage somewhat improved for infantry use.
          .30-06 kept for vehicle and aircraft usage. It might be interesting to calculate the savings in materials, brass, lead, copper, powder over the billions of rounds during the war.
          As the M1 was already standardized, a longer, skinnier case that would allow more capacity might have been a good choice, but the .250 was a commercial cartridge, so it should have been quicker and easier.

          • Unless we’re talking something really crazy like having the SCHV revolution come 20 years earlier, I am not sure any other caliber would be a great idea.

            Due to the nature of logistics of these things, the home team has a huge advantage, if you catch my drift.

          • Grant

            I’ve always thought that the .250 Savage would have been a great choice for a service rifle back when they were adopting the Garand.

          • It was very ahead of its time. One of my favorite rounds ever.

        • Fast Forward

          “Rifle weight would have been a bit better, but still not dramatic.”

          Have you had an infantry load epiphany?

          Load carried in the hands is significantly more taxing than load distributed on the body frame (Aussie study).

          • Sure, but the M1’s not that bad (only a little heavier than a modern M4A1, fully equipped), and the .276 variant was at best a pound lighter.

          • Fast Forward

            “and the .276 variant was at best a pound lighter.”

            Do we have the weight of the M1 in 30-06 to compare to .276?

            What about: flash, smoke, recoil, flinch and marksmanship training time?

          • .276 cal T3 (early model) was 8lbs 9 ounces. The .30 cal T1E2 was 9lbs 8 ounces. So less than a pound of difference, and the T1E2 was more mature than the T3 (weight usually increases during product development).

            Recoil of the .276 guns was surely less. I am one of the few people living who has fired a .276 cal rifle (a Pedersen PB) and I would say subjectively it definitely recoils less than an M1. However, for a semiautomatic rifle the M1 is pretty tame anyway. It’s much easier to shoot than an M1903, for example.

          • Fast Forward

            “However, for a semiautomatic rifle the M1 is pretty tame anyway.”

            It’s; “pretty tame,” because it’s ‘pretty heavy.

            Which calibre do you think John Garand would have preferred to implement?

          • I think Garand, like any good designer, would implement the caliber he was told to implement. In reality, Garand went above and beyond the call of duty and designed rifles from the ground up for both calibers. This among other things sets him apart.

          • Fast Forward

            I seem to recall that the .276 was his first implementation. He had to subsequently make modifications to handle the 30-06.

            I’m sure there are experts on this subject who could probably provide a definitive statement.

          • That is incorrect. The design was begun in February of 1927, according to Bruce Canfield (probably the foremost M1 Garand expert alive), and in .30 cal.

          • Fast Forward

            “Design was begun in February of 1927…….and in .30 cal.”
            That’s probably why it was so heavy.

          • The Pedersen was only ever designed for .276, and it is the same weight.

            Remember, the .276 and .30 cal Garand rotaries were designed from the ground up for their respective calibers. I’ve seen a couple of the .276 Garands in person, they are quite compact and well engineered.

          • Fast Forward

            The Pedersen design was, I believe, from the 1920’s and ‘somewhat’ predated the Garand design.

            Wiki:
            “Testing in the early 1920s led the Ordnance Bureau to identify three rifle designs – the Bang rifle, the Thompson Autorifle, and the primer-protrusion actuated Garand Model 1919 rifle – as promising candidates. However, all three designs were burdened with the high pressure and heat generating characteristics of the .30-06 ammunition, which looked likely to result in a weapon too
            heavy and too subject to overheating to be worthwhile. Trials with a
            small number of “militarized” .25 Remington autoloading rifles,
            despite their unsuitability for combat, provided a body of practical
            experience with semiautomatic rifles and an appreciation for the idea
            less powerful ammunition might be a critical part of the successful
            development of such weapons.”

          • The Pedersen was begun in 1923, and essentially completed in fall of 1925. Very few changes were made from that point until early 1931 when Ordnance tests showed a significant advantage for the Garand.

          • Fast Forward

            “when Ordnance tests showed a significant advantage for the Garand.”

            My point throughout this discussion was that 30-06 was overpowered for an infantry rifle and that .276 might, logically (Vulcan logic), have been the preferred option.

            Interestingly, you seem to be wedded to the conclusion that there was little or no advantage to the .276 and that minor difficulties were insurmountable.

            I have a .276 Pedersen (inert) cartridge manufactured by: Kynoch, Birmingham, headstamp dated 1930.

            Apparently:
            “.276 ammunition manufacture was established in the UK by both Kynoch and Greenwood & Batley.”

            “It was also anticipated that the .276 would, ultimately, be accepted by the US and that UK implementation would follow.”

            It would seem reasonable to suppose that; if the UK could successfully manufacture .276 there should have been no ‘significant’ manufacturing problems for the US.

            It’s been a good discussion and I’ve learned quite a lot, including about Star Trek. “It’s life Nate, but not as we know it.”

          • “My point throughout this discussion was that 30-06 was overpowered for an infantry rifle and that .276 might, logically (Vulcan logic), have been the preferred option.”

            In a vacuum, .276 is clearly better. But vacuums only exist in the lab and outer space.

            “Interestingly, you seem to be wedded to the conclusion that there was little or no advantage to the .276 and that minor difficulties were insurmountable.”

            The advantages of the .276 were insignificant compared to the pain in the rear of changing the logistics system. This is the “home team advantage” that an established round (like .30-06 was) has at work.

            “I have a .276 Pedersen (inert) cartridge manufactured by: Kynoch, Birmingham, headstamp dated 1930.”

            Yeah, the Brits quite liked it. I’ve got something like 20 live rounds of .276 and 5 or more fired cases.

            “It would seem reasonable to suppose that; if the UK could successfully manufacture .276 there should have been no ‘significant’ manufacturing problems for the US.”

            Oh I don’t think there would have been manufacturing issues with the T2. I think the British, with their rimmed .303 round, also had more of a reason to want to switch.

            This isn’t the first time I’ve gotten in trouble in the comments for batting for the “home team advantage”. Clearly, it’s time for an article.

          • An 80% solution we have (literally) trainloads of in stock, and shiploads of tooling for, is arguably better than a 90% solution that we have NO unique infrastructure in place for, *especially* when it is still in development iterations where we can reasonably expect tech, schedule, cost, space, and weight risks to increase.

            Now, a 95% or 98% solution as an improvement is often worth it… if you’re not mired in drastically limited budget cycles because “We ain’t gonna study war no more.”

        • ostiariusalpha

          I still say that you and MacArthur are both completely wrong. The T2 was as much of an idiotic mistake as the .30-06, it gave no justifiable performance boost over the Pedersen cartridge, and only exists because they wanted to use a few of the same brass drawing dies as the .30-06 ammo; that’s nothing more than pinching pennies and losing dollars. There was no money saved by staying with the .30-06 either, the M1 Garand required entirely separate ammunition from the machine guns made on entirely separate production lines with separate equipment. There were negligible savings in using the same brass dies, but that was offset by the increased material costs of the heavier casings, bullets, and powder of the .30-06. Not to mention the increased wear and lower reliability the bigger round imposed on the Garand rifle that was originally designed around the .276 Pedersen. It was a stupid decision by MacArthur, that had zero benefits both in logistics and for the individual soldier. I’d put it a behind his decision not to immediately bomb the Japanese bases in Taiwan right after Pearl Harbor, that let the Japanese launch the invasion of the Philippines virtually unhindered, amongst his top career blunders; but not too far behind it.

          • “The T2 was as much of an idiotic mistake as the .30-06, it gave no justifiable performance boost over the Pedersen cartridge, and only exists because they wanted to use a few of the same brass drawing dies as the .30-06 ammo; that’s nothing more than pinching pennies and losing dollars.”

            Wrong, the T2 existed because the .276 couldn’t meet performance goals when loaded by commercial manufacturers with different propellants. This is in the pre-ball propellant era, remember, so it would have been difficult or impossible for the Army to say “alright everyone’s using IMR 4198 (or whatever; the propellant used for .276 was similar to 4198) now”. There just wasn’t enough IMR 4198 to go around. Same thing happened to 5.56mm and IMR 4475 in the 1960s, too. At the end of the day, remember that it doesn’t matter if you can make 100,000 rounds of the stuff that meets ammo performance goals. You need to be able to make billions of rounds per year. And the .276 FB9892 and PD-42 couldn’t do that.

            “There was no money saved by staying with the .30-06 either, the M1 Garand required entirely separate ammunition from the machine guns made on entirely separate production lines with separate equipment.”

            Also wrong. At the time of the trials, the M1 Garand and machine gun both used M1 Ball. By WWII, both were using M2 AP.

            “There were negligible savings in using the same brass dies, but that was offset by the increased material costs of the heavier casings, bullets, and powder of the .30-06.”

            That’s true but not the point. They would go on to try and recapture this advantage with the .30 Light Rifle which became 7.62x51mm.

            “Not to mention the increased wear and lower reliability the bigger round imposed on the Garand rifle that was originally designed around the .276 Pedersen.”

            Wrong. Garand began the design of his rotary bolt semiautomatic rifle in early 1927, for the .30 cal. Neither the T3 nor the T1 were adaptations of each other, they were both designed from the ground up for their respective cartridges.

          • ostiariusalpha

            “…the T2 existed because the .276 couldn’t meet performance goals when loaded by commercial manufacturers with different propellants.”
            Think about this requirement for a second, even in 1929 they were able to match burn rates to case capacity, so why would they try to load the .276 Pedersen with Hercules and Olin propellants that did not fit its range? When it turned out that IMR1147 wasn’t giving optimal performance in the .30-06, they didn’t alter the case, but instead changed the powder formulation to IMR4320. That’s why the T2 case was idiotic: the commercial propellant requirements made no sense at all, and were not applied in the same way to .30-06.
            “There just wasn’t enough IMR 4198 to go around.”
            And yet that never actually happened. There was never a shortage of either 1147 or 4320, despite the considerably larger powder load of .30-06, and they were perfectly happy to alter propellants that didn’t meet their expectations. An odd bit of hypocrisy that gives the lie to your assertion; when they did supplement 4895 with Winchester ball propellants in WWII, they still matched the burn rate to the case, not the other way around.
            “By WWII, both were using M2 AP.”
            The decision to use majority M2 AP was made in July 1943, and didn’t trickle down to the front lines till the end of that year. The machine guns were still shooting belted M1 Ball well into the end of 1944. Production of M2 Ball for service rifles was begun in 1938, while M1 Ball for machine guns was only ended in 1941. On separate production lines.
            “Garand began the design of his rotary bolt semiautomatic rifle in early 1927, for the .30 cal.”
            Right, I worded that incorrectly. I was just referring to the T3 series as being more reliable, not trying to imply that Garand’s first gas trap rifle wasn’t a .30 cal.
            “Neither the T3 nor the T1 were adaptations of each other, they were both designed from the ground up for their respective cartridges.”
            The .30 cal T1 did come first, but the T3 was obviously an adaption of it to fit the specs of the .276 Pedersen cartridge. And conversely, the T3E2 was adapted back into the T1E2, which has much more in common with it than the T1. There was no reinventing the wheel on either gun, though the T1 series continued to require refinements to the op rod and bolt that were not as problematic on the T3E2.

          • “Think about this requirement for a second, even in 1929 they were able to match burn rates to case capacity, so why would they try to load the .276 Pedersen with Hercules and Olin propellants that did not fit its range? When it turned out that IMR1147 wasn’t giving optimal performance in the .30-06, they didn’t alter the case, but instead changed the powder formulation to IMR4320. That’s why the T2 case was idiotic: the commercial propellant requirements made no sense at all, and were not applied in the same way to .30-06.”

            You’re not thinking straight. First, propellant shortages were a major industrial issue before the advent of much faster and cheaper to make ball propellants. Second, of course they changed the powder formulation for .30-06 instead of the case, the round was already in service Which is easier, liquidating millions or billions of rounds of ammunition and modifying tens if not hundreds of thousands of weapons, or saying “let’s not use that propellant”?

            .276 hadn’t been adopted yet. It was still being optimized. The additional case volume was necessary, not only because of the wartime need for propellant flexibility (which ALL nations up to that time had a requirement for), but also for longer armor piercing and tracer projectiles, which took up more volume in the case.

            “And yet that never actually happened. There was never a shortage of either 1147 or 4320, despite the considerably larger powder load of .30-06, and they were perfectly happy to alter propellants that didn’t meet their expectations.”

            That’s because in the late 1930s and early 1940s the US Army opened a large number of ammunition and propellant factories – something that wasn’t even remotely possible in the early 1930s.

            “An odd bit of hypocrisy that gives the lie to your assertion; when they did supplement 4895 with Winchester ball propellants in WWII, they still matched the burn rate to the case, not the other way around.”

            Calm down, dear. “Hypocrisy”? .276 was in development. .30-06 had been standardized since 1906. These are completely different situations.

            “The decision to use majority M2 AP was made in July 1943, and didn’t trickle down to the front lines till the end of that year. The machine guns were still shooting belted M1 Ball well into the end of 1944. Production of M2 Ball for service rifles was begun in 1938, while M1 Ball for machine guns was only ended in 1941. On separate production lines.”

            Yes, although what your addressing is essentially sloppy grammatical construction on my part.

            “Right, I worded that incorrectly. I was just referring to the T3 series as being more reliable, not trying to imply that Garand’s first gas trap rifle wasn’t a .30 cal.”

            The T3 was initially more reliable because the T1 wasn’t finished until 1932 with the “model shop” .30 cal T1E2s (Garand was ordered to work on the .276 version sometime in 1929). I don’t think I’ve ever seen evidence that the .30 cal T1E2s were any less reliable than the .276 cal T3E2s.

            “The .30 cal T1 did come first, but the T3 was obviously an adaption of it to fit the specs of the .276 Pedersen cartridge. And conversely, the T3E2 was adapted back into the T1E2, which has much more in common with it than the T1. There was no reinventing the wheel on either gun, though the T1 series continued to require refinements to the op rod and bolt that were not as problematic on the T3E2.”

            if by “obviously an adaptation of it” you mean “using the same mechanical principles but with every single element reworked for the new round, then sure. The T3 is absolutely not just a retrofit of the T1, we know this because the T1 wasn’t even finished by then.

            The idea that the T1E2 was an adaptation of the T3E2 is, uh, playing a bit fast and loose with the facts. These were rifles designed by the same man at the same time, so of course there’s many shared elements, and refinements that were being worked into both. However, the T1E2 is much more similar to the T1 than it is to the T3E2.

          • ostiariusalpha

            “You’re not thinking straight. First, propellant shortages were a major industrial issue before the advent of much faster and cheaper to make ball propellants.”
            I’m apparently thinking about this more clearly than you are. Propellant shortages are not solved by forcing the wrong powder into a cartridge. Hercules and Olin/Winchester would have been perfectly happy to develop their own powders for the .276 Pedersen, and as you point out, you can build more factories as they did in reality. Instead they bizarrely specified propellants already formulated for the .30-06, and unsurprisingly resulted that it lost performance.
            “.276 hadn’t been adopted yet. It was still being optimized.”
            No, it was actually pretty optimal already. The commercial powder requirement was nonsense, and reducing the clip capacity and increasing bolt thrust to meet that nonsense requirement was simple stupidity.
            “…but also for longer armor piercing and tracer projectiles.”
            What evidence do you have that the .276 Pedersen case had any trouble with its AP round? Machine guns use tracers, not semi-auto service rifles. The .30-06 was perfectly adequate as a machine gun cartridge, with quite functional tracers. It was the attempt to shoe-horn the Pedersen into machine guns that was a mistake. While there is some virtue to caliber commonality, it turned into a religious tenet here that killed the better rifle round, and never actually met reality during most of the war.
            “Calm down, dear. ‘Hypocrisy’? .276 was in development. .30-06 had been standardized since 1906. These are completely different situations.”
            Adding patronization to hypocrisy doesn’t improve you character, Nate. The point is that the .276 was not improved in any justifiable way by these further developments of the case geometry, when simply developing better propellants worked out fine for the .30-06.
            “…sloppy grammatical construction on my part.”
            This is hardly a serious scholarly debate, I’m not sweating it.
            “The T3 was initially more reliable because the T1 wasn’t finished until 1932 with the “model shop” .30 cal T1E2s (Garand was ordered to work on the .276 version sometime in 1929). I don’t think I’ve ever seen evidence that the .30 cal T1E2s were any less reliable than the .276 cal T3E2s.”
            the T1 wasn’t even finished by then.”
            20 of the T3E2 rifles were tested alongside a .30 cal T1E1, the T3s trucked along fine while the T1 cracked its bolt. Even after strenuous trialling and passing of decades the T3E2 test rifles are still in fantastic shape and fully functional. Garand had to redesign the T1 bolt for the 80 T1E2 “model shop” rifles, and these required further redesign after testing showed more problems.

          • InternalBallistic

            ” “…but also for longer armor piercing and tracer projectiles.”
            What evidence do you have that the .276 Pedersen case had any trouble with its AP round?”

            Non-tungstencarbide AP uses hard steel which has a much lower density than lead. So you need a longer Projectile, this reduces chamber volume a lot, so velocitys get even lower, especially when already having some propellant problems.
            Same goes with tracer, tracers are quite long and reduce capacity a lot.

          • ostiariusalpha

            That’s a cute theory, but doesn’t mesh with reality that militaries that used even smaller calibers than 7mm didn’t have any trouble producing AP ammo for their service rifles. And there were no propellant problems with the powder the .276 Pedersen was actually designed to be loaded with, just when they tried using inappropriate commercial .30-06 powders.

          • Uhhhh, actually they did. For example, the 6.5mm Swede’s AP projectile weighs only 112 grains, far less than the 139 grains of the service load. This means the two rounds shoot to two different points of aim, which is undesirable. However, that was their standard round, so that’s what they had to live with.

            It’s notable that from 1903-1953 (50 years!) NO nation on earth successfully adopted and fielded a new caliber below 0.298″. During this time, many nations adopted new .30 caliber rounds, including almost all of the major 6.5mm users.

            This has a lot to do with the issues in constructing AP, tracer, and other kinds of projectiles in calibers smaller than 0.30.

          • ostiariusalpha

            Except the Swedes weren’t pretending it was a long range anti-materiel round, that was a job for machine guns and sniper rifles chambered in 8x63mm. It was a line of sight, light cover penetrator for the service rifle, where the POI shift was minimal. Seems they didn’t see it as being as much of a problem as you do.
            “It’s notable that from 1903-1953 (50 years!) NO nation on earth successfully adopted and fielded a new caliber below 0.298″.”
            The 6.5x55mm prj m/41 & pprj m/41 weren’t an entirely new design, but it was an update, same as M2 Ball and M2AP.

          • Are you going to contribute anything beyond your opinion that everything was fine and projectile density isn’t a factor? Because it’s come up as a major factor in evaluations of sub .30 cal projectiles over and over and over again. It was a major factor during .276 development, and during .280 British. In fact, it was arguably a primary reason that both rounds were ultimately rejected. Read HWS I and Stevens’ FAL books. Plus it’s something that becomes very obvious when designing projectiles in SolidWorks.

          • ostiariusalpha

            In comparing M61 to M993, yes it was the lesser factor. Density is nice, but it isn’t the only factor that makes an AP bullet more effective.

          • It doesn’t seem like you understand what he was saying.

          • Disqus evidently ate my comment. Short version:

            1. It wasn’t just the propellant issue, it was tracers and AP projectiles too. You’re acting as though the .276 didn’t have to meet the materiel requirements of the time. Of course it does.

            2. Dodging the point. The point is that .276 did not have a major logistical chain attached that would be affected by a dimensional change. The fact that in your opinion it was optimal is of no consequence whatsoever.

            3. You will find the history of tracer and AP development in HWS I, which you really should read before getting into discussions on this subject.

            4. My character isn’t a factor. Everybody knows who I am, I have nothing to prove here.

            5. Read Canfield. What you say about the T1 and T3 isn’t wrong, but you’re missing a lot of context. You need to read more about this subject before you try to debate these things. There’s a lot you’re missing out on.

          • ostiariusalpha

            1. For the 3rd time, tracers have no business in a semi-auto service rifle, period. And as I have pointed out again and again, as a service rifle round, the Pedersen AP was more than effective enough. Any improvement should have been in the direction of making it lighter, as was done with pprj m/41 and M993. Point of impact shift is only really relevant in a machine gun, which the .276 Pedersen should never have been considered for.
            2. They produced hundreds of thousands of rounds; no big deal in the greater scheme of things, but certainly more than the zero rounds of T2 produced. But let’s throw all those away and change to a case design with higher bolt thrust, even though the T1 rifle is showing problems there, and reduce our ammo capacity because, dadgummit, we need caliber commonality with the machine guns. That’s the opinion that had consequence, and it was dumb.
            4. Well, that’s a good thing, because isn’t improving your arguments at all.
            5. So, I’m not wrong, but I need to read more so that I’m “right”er? Sure.

          • 1. Really? Explain the existence of M196, then.Tracers are used in rifles all the time, for various purposes. Just because they are not loaded 5-to-1 like they are in MGs does not mean a rifle cartridge does not need them. So then this is just your opinion, and not a very well informed one.

            You’ve pointed out? No, you’ve just stated your opinion that .276 AP was fine. You haven’t even read the relevant literature on the subject, so what does that count for? Do you know anything about the 1929 tests of the T1 AP bullet, which – despite having a dense tungsten steel core – achieved only 3/5ths the penetration ability of M2 AP predecessor .30 M1922 AP at 300 yards? Do you know anything about the problems with penetration that plagued the .280 round during its development in the late 1940s and early 1950s?

            2. *Sigh* Where to begin? The round was in development, so there was no logistical supply chain, which means there was nothing to throw away. Hundreds of thousands of rounds is nothing. That’s called “a lot” today – as in “all the rounds were from the same lot” (multiple smaller lots of .276 were produced, to be clear – but the total number of rounds was similar to today’s lot).

            Something puzzles me. You’re very adamant that the T2 was this huge mistake because it reduced the Garand’s capacity by 2 due to having a wider case head. Along with this, you insist that the very tangible benefits of the T2 cartridge (its greater propellant flexibility, far greater suitability for AP and tracer projectiles, etc.) are unimportant and stupid optimization criteria.

            The whole time, though, you ignore the reason the M1’s capacity was reduced to 8 in the first place: The using services had a harebrained requirement that the rifle’s magazine had to sit flush with its stock! Kinda makes your objections seem a bit, eh, misplaced, doesn’t it? Maybe you didn’t know about this requirement, but if so, then I reinforce what I said earlier. Read up on the subject. It’ll do you good.

            5. Yeah, you have some reading to do. I’ve told you where to go.

          • ostiariusalpha

            “Tracers are used in rifles all the time, for various purposes.”
            M196 is for select-fire rifles and light machine guns, genius; none of those purposes serve a semi-auto service rifle.
            “Do you know anything about the 1929 tests of the T1 AP bullet, which – despite having a dense tungsten steel core – achieved only 3/5ths the penetration ability of M2 AP predecessor .30 M1922 AP at 300 yards?”
            USN testing showed that M2 AP could penetrate 21mm of an HHA steel target at 300m 50% of the time. With those same criteria, M61 penetrated a 7mm HHA target 50% of the time at 300m. Must be why we never adopted 7.62x51mm.
            The using services had a harebrained requirement that the rifle’s magazine had to sit flush with its stock!”
            They also requested that it weigh 8 lbs, which none of them did. They were pretty flexible about those preliminary requirements.
            https://uploads.disquscdn.com/images/389e600cce52082e115ea1cf1d07ffd3326f8ce4bbc5b63c659053a45f8e0eb1.gif

          • “M196 is for select-fire rifles and light machine guns, genius; none of those purposes serve a semi-auto rifle.”

            No light machine guns in 5.56mm existed when M196 was designed. You just had the AR-15, which was designed as a point and shoot weapon. So, why was a tracer designed?

            More directly, the .276 Pedersen and .30 Carbine both had tracer rounds designed for them, despite both being intended for semiautomatic rifles only (there never was a machine gun chambered for .276, though there likely would have been eventually, and the .30 Carbine M16 Tracer predates the M2 Carbine – and was a British request, of all things!). So, obviously, tracers are necessary for semiautomatic rifles, your opinions notwithstanding.

            “USN testing showed that M2 AP could penetrate 21mm of an HHA steel target at 300m 50% of the time. With those same criteria, M61 penetrated a 7mm HHA target 50% of the time at 300m. Must be why we never adopted 7.62x51mm.”

            There doesn’t seem to be a point to this. You’re just saying M2 AP penetrates more than M61 AP. Who cares? I’m talking about the decisions that were made and why. It doesn’t matter whether you or me or anyone else alive today thinks .276 AP would be fine, it matters what the decision makers of the time thought. And they clearly saw it having inferior ability, and desired a larger penetrator, which ate up space in the case and correspondingly required more case volume. That’s not something that’s hard to understand, nor is it contingent on your opinion of what would make a better round.

            “They also requested that it weigh 8 lbs, which none of them did. They were pretty flexible about those preliminary requirements. ”

            Yet the M1 had an 8 shot mag. It could have had a 10 shot mag, in .30-06 or .276 T2. So where is your passion for that “bad decision”?

          • You know, EVERY SINGLE TIME I used tracer rounds through my M16, I used it in semiauto. Most of the time, I was using it as a fire marker (an amazingly fast and unjammable datalink to my soldiers), with commands such as, “Grenadier, ON MY TRACE!”

          • Brett baker

            So, procurement was as f’d up in the good old days as now?

          • Samuel Millwright

            If anything, it was noticeably worse at several points… The US ordnance department was George Lucas’ inspiration for the Mos Eisley Cantina….i.e. a hive of scum and villiany

        • gunsandrockets

          Please show me the 8 shot .276 Pedersen M1 rifle.

          • They never made it, because the T2 round’s development was never completed. However, that is the round that would have been adopted, and it had the same case base as .30-06. Hence, 8 shots, not 10.

          • gunsandrockets

            “that is the round that would have been adapted”

            Thats sounds at best as extremely speculative personal opinion.

          • It’s not. Read HWS I. It makes it very clear that this was another step in the development of the .276 before adoption. The additional case size was needed for propellant flexibility, as well as armor piercing and tracer projectiles.

            Sure, a 10-shot .276 Garand is an extremely compelling rifle, but that’s not what we would have ended up with.

          • gunsandrockets

            please paraphrase the relevant text

          • Not to put too fine a point on it, but if you’re going to argue with me about this you could at least read the relevant books.

            http://i.imgur.com/LJ5fQw4.jpg

            https://68.media.tumblr.com/c7f9f1ddf249b15e79b86168389eff8d/tumblr_o50s92RMxT1s9a9yjo1_400.gif

          • gunsandrockets

            You have lived down to my expectations for you. That’s a shame.

            You have this bad tendency to pronounce your judgements and opinions as if they are incontrovertible facts. And be smug about it. And you have done it again.

            Let’s look at your conclusion, and see how well it is supported by facts.

            “because the T2 round’s development was never completed. However, that is the round that would have been adopted, and it had the same case base as .30-06. Hence, 8 shots, not 10.”

            Would a tiny change in the diameter of the .276 case force a .276 Garand to use an 8 round clip? No. That is an assumption you made, an incorrect one.

            We don’t have to accept your speculations as to the nature of the .276 Garand, because we can look at the real life .276 T3E2 rifle of which 20 were made for the 1932 field trials.

            The .30 M1 rifle has a shallower belly than the .276 T3E2, and that is the reason the M1 clip is only eight rounds, not just because the cartridge is wider than .276 Pedersen.

            I suspect the Army settled for an 8 round clip to try and cut back on the weight of the .30 M1, seeing as it was too heavy. The Garand .30 T1 rifle of 1930 had a similar belly.

          • “You have lived down to my expectations for you. That’s a shame.”

            I’m not really interested in that. My expectations for anyone seriously trying to argue one point or another is that they at least bone up on the established literature. If, after that, you want to try to make an intelligent and well constructed argument against something I’ve said, be my guest. But I can’t discuss this with you if you aren’t even aware of the basic history.

            “You have this bad tendency to pronounce your judgements and opinions as if they are incontrovertible facts. And be smug about it. And you have done it again.”

            You’re perceiving it that way. Really, I just want you to read the friggin’ books. Then read them again.

            “Would a tiny change in the diameter of the .276 case force a .276 Garand to use an 8 round clip? No. That is an assumption you made, an incorrect one.”

            Projection. Now you are stating that this is incorrect, and based on… What? Talk about “pronounce your judgements and opinions as if they are incontrovertible facts”!

            The rim diameter of the .276 T2 is the same as .30 cal. So the magazine capacity would have to be correspondingly reduced (as it was for the .30). Since a symmetrical reversible clip was a requirement, the reduced capacity must be an even number. Hence, 8 rounds instead of 10. Of course, a larger magazine would be possible, but it is a fact that Garand didn’t do that with the .30, which means we have no reason to believe he would do it with the .276 that shared a rim with it.

            “We don’t have to accept your speculations as to the nature of the .276 Garand, because we can look at the real life .276 T3E2 rifle of which 20 were made for the 1932 field trials.”

            Which is in the old .276 PD-42/FB9892, not in T2.

            “The .30 M1 rifle has a shallower belly than the .276 T3E2, and that is the reason the M1 clip is only eight rounds, not just because the cartridge is wider than .276 Pedersen.

            I’ve seen these weapons side-by-side. The depth of the magazine boxes is about the same:

            https://i.imgur.com/rS34Ytc.png

            “I suspect the Army settled for an 8 round clip to try and cut back on the weight of the .30 M1, seeing as it was too heavy. The Garand .30 T1 rifle of 1930 had a similar belly.”

            See, this is why you need to read the literature. The Army didn’t have anything to do with the 8 round clip of the M1. That was a decision that John Garand made during the design of the T1 (surely with the consultation of other Springfield Armory employees). Maybe it was made for weight, but again, the M1 and the T3E2 are not so far off in weight – less than a pound. Look at the picture linked above comparing the two. They are extremely similar in size. So this massive size difference that would allow a T3E3 T2-firing Garand to have 10 shots, that doesn’t exist.

            Now we are of course in speculative territory. Nobody knows how many rounds the T2-firing Garand would have held. But, it’s worth pointing out, the T3E2 was considered very mature. The change to the T2 cartridge was made very late, and would have been made within the confines of the T3E2 design. This strongly suggests it would have had a reduced capacity to compensate for the wider rim (and that means 8 shots, not 9, because of the requirement for reversible clips). This is all stuff you would know if you had done your reading. But you haven’t, so now I must take the time to tell you.

            Please, go read the sources I have pointed you towards. HWS I, Canfield, Stevens, etc. If you haven’t read your Hatcher, certainly do that as well. It will shed a lot of light on the problem for you.

          • gunsandrockets

            Did you even bother to do the math between the different .276 cases? And how much difference that might make to the size of a 10 round .276 clip? I did.

            Did you forgot the Forgotten Weapons video on the .276 T3E2 rifle? How ironic. Since it very helpfully laid out a .30 M1 rifle side by side for a detailed comparison. And the difference between the profiles of the rifles forward of the trigger guard are glaringly obvious.

            But you can’t see any difference. Well. I can’t help that you are blinded by your bias.

            Say, how about another sneer gif?

          • “Did you even bother to do the math between the different .276 cases?”

            I have SolidWorks models of both of them.

            “And how much difference that T2 case might make to the size of a 10 round .276 clip? I did.”

            Cool, so did I. Doesn’t change the fact that you’d be looking at either substantially re-working the design or accepting a loss of two rounds. And it didn’t seem like they were willing to do that at that stage.

            “Did you forgot the Forgotten Weapons video on the .276 T3E2 rifle?”

            …You know that image I posted is a screenshot from that video, right? That video, which I wrote a whole article on…

            “Since it very helpfully laid out a .30 M1 rifle side by side for a detailed comparison. And the difference between the profiles of the rifles forward of the trigger guard are glaringly obvious.”

            If you actually measure on your screen, you’ll see they are about the same depth. Plus, I mean, I’ve seen these rifles in person. They are about the same depth.

            “But you can’t see any difference. Well. I can’t help that you are blinded by your bias.”

            While you are enlightened by your own intellect, yes.

          • And I think at this point I have wasted quite enough time telling you information you could have gotten for yourself by reading a few inexpensive and readily available books. So the rest is up to you, I’ve got other things I need to take care of.

          • Brett baker

            Why Don’t you just point out WW2 ended 72 years ago? And OA I read MISFIRE,too, but I Don’t consider it 100%accurate.

          • I agree, Misfire has several errors. I don’t normally reference it.

        • Samuel Millwright

          Eh…. Personally i still believe Melvin Johnson actually had the right of it since HIS rifle and LMG could both actually use the millions of m1 spec 30’06 rounds in storage…. Right off the 1903 stripper clips to boot!

          So in the sense that his rifle and lmg could both actually take advantage of the ostensible reason for staying the course in the first place, he definitely wins.

          • The M1 Garand was designed for M1 Ball. It can fire that round just fine. M2 came later.

        • marathag

          When making billions of cartridges, that slight saving on each round would add up to be worthwhile, and the existing stocks of 30-06 weren’t even used in the Garand, anyway.

          • Sure, but embarking on a major logistical change right when the Depression is getting going really doesn’t make a lot of sense.

            They did revisit the concept, though, and I think there is a very compelling case to be made that 7.62mm NATO was seen as the “perfected” version of .276 by Studler and Frankford Arsenal.

            Of course, I also think adopting 7.62mm was a mistake, but hey.

          • marathag

            FDR liked Keynesian spending, that government spending brought increased employment, and from that, increased prosperity. It’s not like he was going to order existing stocks of 30-06 to be destroyed, as plenty of Springfields and Brownings could use it

          • Erm, no, the US Army’s budget at the time was in the toilet. Hell, they had to court the Navy with the M1 to even keep the program on life support. The program was very nearly cancelled in the early ’30s. If they’d gone the .276 route, that very well could have been the straw that broke the camel’s back.

            Please, I recommend everyone here read the relevant literature! Canfield, HWS, Stevens, etc. A lot of what is being missed is in there. Canfield in particular is extremely detailed in his history of the M1’s procurement. They simply didn’t have the money for a new round. They didn’t even have the money for a new rifle, but they managed to string the program along enough for things to get better in the late 1930s.

      • I should clarify that I agree the .276 is closer to the ideal. It’s just not different enough from the .30 cal. to justify adoption, even in retrospect.

    • Kaban

      You do realize that after 6.5×47 (an excellent round, by the way) gets adopted, AR’s are upped to AR-10 action length, mags, etc., whole Army supply line is cleared and refilled with millions of parts, Lake City (or wherever ammo is made) is retooled and whole European NATO countries are bent over and…convinced to do the same, expenses will mount to a number which might just eclipse much-spanked F-35?

      • Rifle

        Incredible debatable what “excellent” then means… Urgh

        • Kaban

          Of course. It is exceedingly poor choice for 10m 3P rifle competitions and as anti-material round.

          • Rifle

            Excellent is what was the rest of youre statement on cost and logistics.

      • Fast Forward

        Take a look at POF Revolution.

        • Kaban

          >>Take a look at POF Revolution.

          I did. Somehow the rifle still needs different lower, because of longer round and mags.

      • Nunya Bidniz

        Yes, all of that will easily add up to the cost of *one* F-35. So we continue flying the B-52 for another 20 years to make up the difference… 😉

  • Nicks87

    So if you could produce a lighter polymer case would it make sense to go bigger than .224? Or would you keep .224 and the polymer case with the increased weight saving benefits? Plus, bullets with some sort of anti friction coating may be the future as well.

    • PK

      It depends. If you go larger, you end up slower, unless you increase case capacity and length, but that has effects on barrel life, and so on…

      Turns out, designing things in a “perfect” way is really, really difficult and usually open to interpretation. That was the point of the article, I think.

    • My opinion is that the lightest round that meets the requirements is the best, but I guess I can see where other people are coming from.

    • Keep in mind that meeting the same kP (performance) with a larger caliber, regardless of case design, will almost always buy you more recoil and bulk (not always, but almost always).

      Both are important, even though you’ll rarely cube out ammo before you go over weight in logistics, ammunition volume DOES affect *receiver* size and weight. And extra recoil is almost always bad (there are some edge cases where it *isn’t* bad).

  • Big Daddy

    I stopped reading at 6.8. This is so biased as to be idiotic.

    • You should have kept going, then. :/

      • Twilight sparkle

        Lol maybe they aren’t a Star Trek fan

      • Big Daddy

        I suggest a new title to be “practical application verses operating in an engineering vacuum”, that would have been more appropriate.

        It’s when both meet to solve a problem does it become useful. You never served you don’t know, period, end of story Nat F. You always take the side of the engineer and discount the people who do the job. That’s the way large ineffective entities work like the government for instance. Unless you have input from the user end it is just nonsense and usually becomes a money pit.

        Take camo for instance. Ask any experienced soldier/marine and they will say it’s useless, the first and most important thing is to breakup your sight picture. Yet the DOD spends millions on useless camo experiments and picks the one that pretty much lost the test. That’s how your approach works.

        The new M855A1 round works great but it’s requiring new magazines and excessive wear on the rifles that use it. There ya go, that’s what engineers will do. That’s the “The surgery was a success but the patient died” mentality.

        Do a tour in a combat environment and come back and do these idiotic articles. I’d be much more interested in your opinions if you did. I see your types in sports, specifically football, NFL fans, they have never coached or had any position within an organized football team and they talk nonsense. They spout stats when the only stat that matters is wins and loses, they ignore how those teams got those wins. The best team does not always win for a reason and people without the ability to include the unknown factors will never get it and understand the big picture.

        You always ignore practical application and put your faith in numbers and that will equate to a failure everytime. The universe does not answer to a decimal point.

        • Ballistics

          Yet he knows serval hundret times more of what a grunt or even marines know about ballistics. That is a simple FACT. Knowing the energy required to penetrate a human body at range does NOT include having killed someone. He has also studied on what historical worked on the battlefield, what in todays time, is educated in terminal ballistics, penetration, as well as what trajectory and drift is acceptable. He read dozends of both military and private written treshhold supposals, as well as established his own. Looking on them they make a lot of sence, bring anyone serving and let them explain whats supposedly doesnt.

          Beeing in combat once does NOT CHANGE DAMN PHYSIC LAWS.

          In what should we calculate rounds instead than numbers?!! Fellings i suppose.

          Pathetic! What a disgrace…

          • Big Daddy

            No the pathetic disgrace are people who sit back and tell others what is best for them. Case in point some pencil neck geek or engineer telling a guy in combat laying his life on the line everyday getting shot at what is best for them. Here use this wonder gun it’s great and the poor grunt is stuck with some POS that might get him killed. It has happened countless times in the history of war. That is a fact. Hey we can save 10 cents or some other disgraceful thing that puts the average combat troop’s life in jeopardy. Y’all have the same elitist mentality and that is a disgrace.

          • Aono

            So your tender emotions count more than hard numbers because elitism. Got it now, thanks.

          • Big Daddy

            Oh the Nat trolls have come out, be careful. They attack with their perfect Vulcan logic. On the street we have names for y’all that fit perfectly.

            I embrace technology, logic, engineering and so on but I temper it with reality and practical application. Some people just do not get that or understand it.

            This place is turning into a millennial run joke. These articles are a joke. I guess ya gotta make money to run this site so y’all come up with junk like this.

          • Aono

            People who served cringe at those who wield their service as a cudgel in an argument. You malign Nate’s lack of service, how a combat tour is a necessary precondition to having a valid engineering and sound logical argument, and now you talk tough again on the internet about “the street.” I’m here to tell you that absolutely nobody here who has served is impressed with this. You beclown yourself.

            Everybody else is cringing because John Browning and John Garand, whose small arms you surely revere, are from exactly your category of “pencil necked geeks” whose opinions everyone is apparently supposed to ignore. Take a powder.

          • Wolfgar

            I have to say this has been a very amusing discussion to say the least. I think Nathaniel’s approach to this topic was quite brilliant and relevant. Big Daddy should lighten up a little since this is all hypothetical and opinion based, “hence the Firearm Blog” not the house arms senate committee discussion with the joint chiefs of staff LOL. That said Big Daddy did bring up many points I completely agree with which I find also very relevant and true. What works well on paper does not always work well in the field.
            Carry On!

          • Aono

            What’s amusing is how the entire article was a very gentle Spock vs the BUTMUH270 mindset vignette, and then BUTMUH270 just had to show up in full assless chaps. Of course all concepts must all go on to be proven in the crucible of the real world. But pointing that out isn’t sufficient to invalidate a concept in and of itself. For that there has to be some sort of counterhypothesis in the context of some meaningful thresholds of success or failure. Instead, we get:

            b-b-B-BBUTTMUHTWOSEVENNDEEEEEEEeeeeee….

          • Big Daddy

            Thank you that’s my point. The end is what works in the field by the people that use it period end of story. Not what an engineers says because his little program for the computer spits it out. But these people do not get that. If they had to use it they would since they do not the whole concept is lost on them and they will go down in a fireball to prove their point. Over time and time again it has happened going back to the civil war even the B-26 Marauder and it’s short wings causing the death of so many young flyers.

            If you design a gun and ammo to be used against a charging Grizzly bear you want to be sure in fact that it is effective or it’s going to cause deaths. Don’t tell someone to bring a glock 20. If you design a combat round and rifle you want to make sure it has as good combat effectiveness as it can without sacrificing certain other things. Weight is a consideration but not over the effectiveness. The M16 was not designed as a battle rifle but it ended up one and that was a mistake compounded with year after year of trying to tweak it so that it actually is.

            I don’t know the feeling of shooting someone but I do know the feeling of hitting someone hard and them not going down. Hit someone hard with a combination and they just sneer at you, how about hitting them a few times with your m4 and them just keep on coming at you. I would quickly lose confidence in my rifle and ammo. I doubt any of these commenters have either experience. Yet they seem to discount it…….this I find to be very distasteful.

          • Aono

            “Drilling holes in skinnies” is a problem of projectile design (check Nathaniel’s fleet yaw articles) and no one here is advocating SS109. Projectile design matters vastly, vastly more to terminal effect than caliber.

            This entire article is devoted to the pursuit of effective cartridges so it takes projectile construction off the table by keeping it with a modern standard and identical across all examples. Hitting something somewhere hard enough to put it down is the whole point of this. And your problem is that no one is worried about that problem. OK.

          • Ballistic

            Someone hit by M855A1 propably cant even tell you the diffrence to 6.8SPC. Storys of M855 icepicks would be even much worse and often with the hilariously slow 6.8spc fmj’s, they tumble even later.

            And this .224 NF has 200-300 Joule more.

            Also .243 NF EPR has 2238 Joule, just as 6.8SPC. While atleast actually hitting at higher range with high percentage (far flatter trajectory and less winddrift), far higher MPBR. And MORE damn energy at range. What do you have to say against that?

          • iksnilol

            So you don’t know what’s it like to shoot someone, yet you know what’s it like to shoot someone and them not going down?

            I’m drunk now, but I doubt we can blame that for your incoherency.

          • Big Daddy

            Yes I do cringe sometimes. It’s your opinion and that’s fine. I can line up many who disagree with you and other so called experts. Since I live near Ft. Hood it would be a long one. I can tell ya what to do with that powder.

            I talk with many combat experienced people everyday. I also talk at length with people serving and that own contracting companies. In fact I did yesterday, he’s usually in Africa and the middle east.

            I base my opinions on my experience as a soldier and avid shooter as well as that of many people who must put their lives on the line and have for many years and on many levels. Both LEO and military.

          • Ballistic

            Then ask them for treshholds at range. And Nathaniel calculates what reaches it in all those calibers, the result wont be suprising, but wont satisfy youre feelings.

            Required:
            – Penetrate ?mm mild steel plate at ?m and cause lethal wound

            – Fragmentation out to ?m

            – Point-blank range no less than ?meters

            – Drop at ?meters no greater than ?inches with MPBR zero

            – Windage at ?meters no greater than ?inches with MPBR zero and 10mph crosswind

            Now do it! Ask them.

          • Samuel Millwright

            Yeah you do act just like a millenial with your huffy stomping around because people who actually know their sh** UNLIKE YOU won’t jjust shut up and do as their told when you imperiously declare the facts to be meaningless…

            Go back to your safe space b****

          • Ballistic

            FEW people on this world even know what is actually best and how to create it. Soliders will take YEARS to learn all this and to develop such a round to begin with. Whats youre god damn point. Hes not telling you or anyone else anything what to do, he just wrote this article.

            And even if he would give a much better solution in every way than all the stupid preference based engineers around which rounds totally underperform. So this would give the actual solider on the ground the best possible ammunition for him to survive of those options.

            Ofcourse a someone with worse ammunition can kills someone with better, no question. The point is, when spending millions over millions to adopt a new round, what will happen sooner or later. Do NOT waste incredible amounts of potential because of stupid preferences that make absulte no sence and will perform worse, and also cost more too. Why in the world buy a worse, more expensive round.

            Thats it!

            I dont think you would really say feelings are better than reality.

            Also the topic itself can be just interesting to people who arent yet in this.

          • Ballistic

            * sry “a” and “s” where just typing errors

          • Y’mean like John Browning, or John Garand?

            Not that I’m anything like them, I mean. Just saying.

          • Big Daddy

            Oh so you know Browning and Garand personally, interesting.

          • StupidityAward

            <- dumbest comment of the internet today

          • What? No, I’m saying they weren’t military men either.

          • No one

            Neither was Hiram Maxim or his son.

            And those talentless hacks ever invented was the first self powered machine gun and the first firearm silencer.

            When have those ever been useful.

            Or that Richard Jordan Gatling charlatan before him who only invented the Gatling Gun, useless.

            Ronnie G. Barrett, Founder of Barrett FM who had no experience manufacturing or engineering yet designed his first rifle by himself that became a massive hit with militaries everywhere? that was a fake story, never happened,

            Gaston Glock, also had never seen the internals of a gun, chief designer of what literally started an event in pistol design known as “The Aglockalype” that made pretty much every other pistol manufacturer follow his design? When has this guy ever got a military contract.

            As you can see, He’s clearly right, you have to be a soldier to design weapons and ammunition that fit the needs of warfare!

            Or it could just be that Big Daddy just took the record for biggest level of the Dunning-Kruger effect from TFBs commenters and should stop posting forever.

          • [Waves hand]

            Infantryman turned engineer here.

            You’re laughably misguided and wrong.

        • Aono

          “Input from the user end” are the requirements. The only “problem” with Nate’s example is that the Vulcan had to flesh out his own requirements regarding external ballistics and penetration and fragmentation thresholds. But if those requirements had come from a committee of experienced end users who are steeped in “practical application,” and who had expressed them as a set of absolute requirements, rather than being worked up implicitly by the Vulcan as a set of relative requirements to measure the rounds against each other, you would have no point at all here.

          And even with that caveat, your only point seems to be that “the tides go in, the tides go out, you can’t explain that.” Cool story bro, enjoy the 45 FMJs and 30-06 en blocs that fuzzy your tender fee-fees in lieu of putting the effort in to engage your brain sufficiently to come up with an argument that comes up with anything measurable, repeatable, verifiable (psst: that’s called “science”).

          But since this isn’t an article on the entire procurement process but rather about philosophies of engineering design, I’m willing to give him a pass on the Vulcan having worked in too great of a requirements vacuum. Barring an end user having set those explicit thresholds for him, working up those thresholds relative to a set of iterative candidates is a great approach if you’re looking to innovate through optimization within given parameters.

        • Well, I guess I struck some kind of nerve with you…

          • Big Daddy

            This goes back to the whole 6.8mm SPCII thing. Not a nerve just the typical personality type I find distasteful, no humility and no thought to anybody that doesn’t have your views. You never served and you show a lot of that looking down your nose at those who do. The types who do not know the engineering end yet have to use the equipment they are given. You do not understand because you never had to do it. If you did your views would be tempered with the reality of those who do. This shows every time you do an article about military arms. You do not wake up every morning with the memories and pains most ALL have to endure and it shows. When it is mentioned you with the flick of a hand dismiss it, that is what I find distasteful. Like you know better because you understand the complexity of it, you don’t know better, you know nothing if you dismiss that and you do all the time.

          • Hahahah, buddy you don’t know a thing about me or what I’ve been through, but boy you sure don’t let that stop you from holding a grudge, do ya?

          • Big Daddy

            Nope I do not and I don’t care to. Who you are is apparent, you’ve done nothing to make me see or feel differently. I just don’t like you and for good reason.

          • Cool. Take care, then.

          • iksnilol

            So you whine about him not caring or knowing about you, yet you dismiss him asking whether you know him?

            Bottle of vodka, says “hypocrite”… and I’m inclined to agree with the commie bastar.

          • Ballistic

            6.8SPC is pure cancer and utter bull**** that so hilariously underperforms its not even funny anymore.

            He can change views and did, but not if the argument is utter senceless bull**** and against all basic physic laws.

            I wonder why hundrets of people with sence here agree with him on basic physical facts, and youre pissed because you got a bunch of salt in youre p****, just because some articles dont fit youre personal preferences.

            And as he said, you have no idea about him.

          • Aono

            The fact that you become personally offended when confronted with an intellectual challenge of any kind might only be a sign that you resent the effort of thinking at all. If you feel condescended to now, that may be because you’re accustomed to sitting on a high horse. What we’ve read from you so far is a truckload of misguided grievance, one lacking in any coherent assertions, or shred of evidence offered in support of same…

            …but…
            …muh…
            …twosevenduhhhh….

          • Big Daddy

            You prove my point.

          • Samuel Millwright

            Funny thing is…. Weaponsman… That’s a guy who’d been some places seen some sh** and downright knew his sh** to boot…..

            Weaponsman would have vehemently disagreed with every single thing you PRETEND to know about firearms fighting AND Nathaniel…

            You ain’t no weaponsman dude and your “confidence” in yourself and your knowledge is as misplaced and ass backwards as everything I’ve ever seen you say anything wrt firearms fighting and or Nathaniel…

          • Eastbound&down

            Why does this remind me of Kenny Powers I can’t stop yelling?

            Google it.

        • CommonSense23

          So what are you suggesting, with all your considerable experience.

          • knuckdownpuwahh

            6.8 spc ofcourse

          • Big Daddy

            Ignoring your sarcasm, what I suggest is when people talk about any firearm that has to be used by someone they take into consideration who has to use it. They have a set of parameters that are constantly ignored by certain types of people who design these weapons. Especially those that never did it. I see this constantly in the firearms community as well as a lot of other aspects. Companies like Colt are notorious for it and are lucky to still be in business. Big green does this all the time yet the Marines are always trying to improve the combat infantrymen while handcuffed by their budget. The marines approach is much more considerate of what will help the effectiveness of their infantry units. We all knew it and talked about it, it was obvious that our lives meant little to so many in charge especially the bean counters and pencil neck geeks, we were just a number. Even in law enforcement, sticking the NYPD with those horrible Glock triggers, although extreme, a perfect example.

          • Aono

            Parameters like… effective to 600m? Maybe you could begin by describing what you think the parameters should be, rather than whinging over how badly it hurts your feelings that no one pre-solicited your opinion. Here I am, soliciting your opinion. Just be prepared to be disappointed because you were the last one in the room to discover Mk262 (the reason 6.8SPCII was stillborn) or Brown Tip.

          • CommonSense23

            How do you get the Marines approach makes any sense? The people who fielded the M45 and M27? And what are you complaining about. The fact we should let servicemen who don’t have any clue what they are talking about have more input?

  • randomswede

    “The math for the lethality requirement reduces to a simple flat figure of 820 J for every caliber.”
    Simple indeed.

    The use case should probably also include:
    > desired barrel length(s) (.300 blk vs 5.56)
    > desired rate of fire
    > powders available
    > budget
    > is the organization to be armed a large force with little training or a small force with extensive training
    > is the round to slot in, in between other weapons or replace everything handheld

    There’s probably more but .

    I’d say that if the Vulcans adopted the .224 and the Romulans the 6.86, the Romulans have more room for future changes. Such as heavier bullets for subsonic use or a very light sabot round for extreme velocities, as well as scaling down an existing weapon is generally to be preferred over scaling up (AKM -> AK-74 AR-10 -> AR-15).

    The main questions should be: What’s being replaced and what are the shortcomings, is there only room for one round, caliber, powder charge, bullet type, etc. or would the problem be better solved by two new rounds and a new delivery truck.

  • yvette99

    This is a false dichotomy. The design of the “process” is just as subjective as the choice of preferences. Not to mention that step 1 of the “process” is just preferences in disguise.

    • Yes, that’s something I mention in the conclusion, and will talk about in greater detail in the follow up. However, it is harder to express your bias in the final product with a process driven method.

  • Hernando Cardona

    Did they beat you up in school because you knew how to speak Klingon? Is this how you justify it all? (kidding)

    • Hahahah. Click-phlegm-blat? Is that how you speak Klingon? I dunno, lol.

  • Johannes von’ Strauch

    Include Recoil! You now already have the powder charge weight for that. Great Article, this is an extremely important topic, i often come across the people using the first type (preference driven), and absolutly nothing good comes of it. Its also verry good you did not gone to say a certain diameter is the best, because this can of course greatly change with different construction, twist rate, and cases. PS: Don’t you think 69000psi is a bit much? Especially with traditional cartridges and propellant the throat and barrel erosion as well as heat stringing will be rather suboptimal

    • 56,000 CUP in Powley is a hack to generate the kind of performance you get with slow burning St. Mark’s propellants like SMP-842. They would not actually produce 69,000 PSI.

      I mean, that is me doing terrible, terrible things to the Powley computer, but it seems to work OK.

      • Johannes von’ Strauch

        Yes, did read it a sec ago above. I know the struggle of recreating rounds that use diffrent powder than usual IMR such as M855A1, i feel with you.

        But then be carefull with the propellant charge weight for recoil, at that pressure it might be lower than SMP-842 on normal pressure. Maybe you instead can just create a modifier by comparing M855A1’s IMR charge in powley and its normal SMP-842 charge, as you did with CT on delphiforums.

        “doing terrible, terrible things to the Powley computer” totally made my day haha.

        • I calculated effective propellant charges using the loading density of M855A1 and the net capacity of the round in question. You’ll note the charge masses shown in the weight section don’t line up with the Powley results.

          • James Kachman

            Speaking of M855A1, I think we were promised a proper fragmentation velocity calculation at some point? 🙂 (Teasing, teasing)

          • Johannes von’ Strauch

            Yes right haha, didnt heard it yet. Not calculation but rather a gel test.

            One is sure, it wont open at 1333fps as far as ive seen. But thats beyond 700yards anyways.

          • I’ve got two separate teams working on it, so yeah. At some point.

  • MateoATX

    As always an interesting article Nathaniel.

    Couple questions – in the pressure column of the load computer, what does the second “Pressure” box at the bottom center of the readout indicate? The value there is usually 69,000 psi.

    Also, why do you mix unit systems? It’s know to cause hypertension in a subset of the population.

    • Johannes von’ Strauch

      Its verry common in ballistics, there tend to be an unwritten but common unit nomenclature, it can ofcourse be personal preference too. Also a lot of it can come trough calculator imputs and outputs, you adopt to them if you is it a lot.
      I prefer grains for projectile and propellant weight, its much finer, also fps over ms, both also are used in most calculators, and if you look up things almost everything is in it, otherwise you have to translate everything to grams and meters per second. I also like psi much more over bar.

      Tough i prefere Joule for muzzle energy, but ftlbf as impact energy at range. Because i know the muzzle energy of all typical cartridges in Joule, but when calculating impact energy at range the default output is ftlbf, so thats just what my mind has adopted to and is practical for me. I calculate case and overall round weight in grams, this is both common and i again know all other round weights mainly in grams.

      And to your first question, PSI is a pressure unit (pound-force per square inch), CUP is Copper units of pressure, using the measuring method of a copper crusher. Replaced often by piezoelectric measurement now.

      • MateoATX

        Let me rephase the first question, why are two different PSI results reported in the load computer results?

        The question about units systems was a shout-out to the tags NF attached to the article.

        • Johannes von’ Strauch

          CUP is an input field while PSI is an translated output. You eighter enter projectile weight, diameter, barrel lenght and pressure. Wile the relation of overall case lenght, projectile lenght and case lenght just calculates the reduced overall chamber volume thats left (the projectile seated into the case takes up volume).

          Then you eighter choose a velocity, or when restricted to an existing case use the given case capacity.

          With the chamber volume (H2O in grains), the reachable velocity will then be shown as well as the propellant charge weight (less propellant means less weight and recoil).

          With a velocity in mind you can just up the case capacity until you get youre velocity. Then you use this required capacity to calculate the cartridge size and weight.

          The CUP input has a small checkmark, if you click that the pressure stays locked, the velcoity and propellant charge goes up or down when changing case capacity. If you dont activate it the velocity stays and the pressure increases or decreases, doing so is only usefull for hot handloads and otherwise could be dangerous as well as greatly increase barrel erosion.

        • One is CUP, one is PSI. Those are different units and have different values for a given pressure.

    • I wouldn’t pay too much attention to the pressure limit I am using, it’s a bit of a hack job. I use 56,000 CUP because if you enter the data for M855A1 you need 56,000 CUP to match its specified velocity (3,090 ft/s) from a 14.5″ barrel. So I just used that value for all of rounds here, as a sort of approximation of St. Mark’s propellants. It doesn’t mean that is the pressure they would actually have, and I am going to cop to going “off the reservation” a bit in that way. But it hasn’t bit me in the butt… Yet.

  • Audie Bakerson

    Humans would take a proven design already in commercial production and tweak it slightly to meet their needs. It was good enough for killing Kzinti.

    • Palmier

      Comment of the day

    • Your Niven/Pournelle reference makes me sad. The good kind of sad, but still. :(““

  • Audie Bakerson

    Humans would take a proven design already in commercial production and tweak it slightly to meet their needs. It was good enough for killing Kzinti.

  • DESTRO

    Whats the mathematical process (formula) for scaling the projectiles between the calibers?
    Say using a .224 77gr Match King.

    • I scaled them via SolidWorks, but you can do it by taking one diameter over another and cubing it. For example, if I want to scale a .224 cal bullet to .308, I would do (.308/.224)^3.

      • DESTRO

        Nice thanks!

  • ActionPhysicalMan

    It is nice to read the work of a thoughtful writer rather one that just says watch me shoot this cool gun or my favorite gun is…. There are way to many of the latter and too few of the former.

    • PK

      Amen to that! Nathaniel’s articles are usually quite enjoyable, and tend toward the technical side of things. I always read them.

    • Rick O’Shay

      They could make the entirety of TFB just James and Nathaniel and it would still be very, very enjoyable. My two favorite contributors, by far.

  • Sean

    Then both soldiers are immediately wasted by a PKM 650 meters away.

    • LMG

      No, a LMG in this caliber would have fire superority over it (much less recoil, much more rounds) as well as propably a flatter trajectory and less wind drift.

      Good joke tough with the 50meters more.

    • Kaban

      Now you know what 7.62 AK’s “800 m” setting is for!

  • Twilight sparkle

    Hmm is it just me or does the case length and cartridge diameter on the first two line up with 204 ruger, 223 Remington?

  • George

    Kirk: immediately grabs nearest M-4, gets to work.
    Picard: thinks for second, grabs nearest M-4, gets to work.

    • ARCNA442

      Picard: thinks for a second, consults his bridge officers, attempts diplomacy several times, grabs nearest M-4, gets to work.

      • LCON

        Sisko: Shoots the bastards with M4 Yells at someone.

  • wetcorps

    I must say I seldom have time to read your whole posts, but I always enjoy reading the titles.
    I think we’re nearing the point where you will be able to gather the titles from all your previous posts into a single text file and publish that as a standalone post.
    No one would notice 😀

  • James Bridges

    It’s an interesting comparison in methodology, but it seems a bit incomplete without consideration of momentum and projectile material. By setting a simple “fragmentation” threshold without consideration of the penetration of those fragments ( not to mention some barrier penetration)it is easy to overlook those factors. Another additional element worth looking at is bore through-volume for a desired barrel length. Shorter barrels will favor the larger bores .

    The Vulcan rounds are very similar to the 6mm SAW, .264USA and .280 British though.

    • LMG

      How in hell is 2960fps similar to 2500fps..?

      “Another additional element” – its already accounted for in the interior ballistic calculator…

      • James Bridges

        First I said similar, not Identical , and the 6mm saw was close to 2700 with a really long 105gr bullet

        Missed the barrel length on the calculator, thanks.

        • LMG

          2700? No. Not even from a 3.5″ longer 20″ barrel.

          Barrel lenght and diameter.

        • 6mm SAW had a MV of 2,550 ft/s.

          • LMG

            + from a longer barrel

          • James Bridges

            Have seen it listed at 2450(Weaponsman) ,2520(wiki), 2550( you guys) and 2600-2700 (older print articles). I believe the latter, simply due to the case volume.The 6 mm whisper runs 2250- 2300 with 105’s just as a comparison.

          • 6mmSAW

            6mm whisper could use diffrent pressure…?

            Give me the chamber volume and i calculate it.

          • James Bridges

            The case capacity is right around 25gr h2o, depends on whether formed from 221/223 or5.56

          • 6mmSAW

            Thats a suprisingly low capacity. Gives a velocity of 2318fps for 55000psi from a 16.5″ barrel, if i not entered something wrong. 2364 for 58000.

          • James Bridges

            That’s why I would expect a higher velocity from the saw, think the pressure limit is around 52,000 for the whispers and blackout, but not stanardized so…

          • 6mmSaw

            Corrected: 2700fps = 42.15grains of capacity left over ofter seating for 55000psi and 39.11grains for 58000psi. From a 16.5″ Barrel – But even with this corrected slightly longer bullet, it has a boattail which means earlier gas leakage so the the +4fps over 42.42 doesnt play any role.
            2320 and 2367 for 25grain full capacity.

          • 6mmSAW

            edit: used a bit to short bullet lenght, i recalculate it

          • 6mmSAW

            Dude it needs a capacity (when the bullet is seated) of 42.42 grains of water at 55000psi and 39.34grains at 58000psi. From a 16.5″ barrel. More than the case capacity of even 6.5Grendel without a bullet.

          • James Bridges

            It had case dimensions similar to the 6.8spc, which is what 42gr capacity?

          • 6mmSaw

            No 34.8–36.9 grains depending on manufacturer.

          • James Bridges

            Look up the various 6×6.8 wildcats, guys running 85’s at 3000….

          • 6mmSAW

            Wildcats often are at high pressure. Also highly depends on barrel lenght.

          • It was 2,450 ft/s very early in development, then it was bumped up to ~2,550 ft/s. I think 2,520 may have been an instrumental velocity, but I’d have to check.

          • James Bridges

            Thanks, that might explain a bit!
            Any idea what the case capacity was like?

          • Just about 35 grs H2O, off the top of my head.

          • James Bridges

            So right in the middle of the 6.8 range, if the velocities are that low I wouldn’t be surprised if a few inches of barrel increased them significantly, just hard to make that jive with what guys are doing with 6.8 based wildcats.

          • 6mmSAW

            2481fps then at 55000psi from 16.5″. Really close to what i was saying. You see just trust me.

          • James Bridges

            Ya know, internet…. lol

          • Just got home and checked my SW model of the case, it has 34.5 grs H2O capacity. However, the steel cased variants may have had a slightly greater internal capacity as steel case walls are often slightly thinner. I haven’t dissected one of my rounds to find out, though.

          • James Bridges

            Thanks. The bore through volume, is what is getting me here. To get the velocities you set from16″, you’re burning a lot of powder and kinda hitting a wall on the smaller bores( what I was getting at in my first post). Thats why the case size is larger relative to the projectile then decreases until you hit a sweet spot and grows in proportion after that. If you change the energy requirements or the barrel length the sweet spot will move. Shorter barrels or more energy will move it to larger projectiles.

          • Correct. That’s why the “optimum” Vulcan caliber is not the “right answer” for the real world. This is really about demonstrating the process, not pointing towards a solution.

          • James Bridges

            Also re reading, that is also really close to the Vulcan round. Lower pressure on the SAW?

          • Much lower, and the propellant’s not as good.

          • James Bridges

            Thanks for all the back and forth. Appreciate it.

          • No problem.

    • Projectile material was considered. All projectiles are three piece EPRs with golding metal jackets, hardened steel penetrators, and copper slugs.

      I didn’t just set a frag threshold either. The 820 J limit comes from a calculation that approximates the depth of penetration of the fragments. It’s by no means perfect, but for this example it doesn’t have to be.

      • Cu

        Do you use pure copper or something like CuZn5? And what density you use.

        • I just use SolidWorks’ “Copper” material, which I assume is supposed to be pure copper. It has a density of 8.9 g/cm^3, which is more similar to CuZn5, though.

          https://i.imgur.com/HJ9qcsZ.png

          • Cu

            Thanks. Thats a bit less scientific than expected. Pure rather seems 8.92 to 8.96 while as example CuZn5 has 8.86 g/cm³.
            But that might be a good slight unerestimation for slight impurity. And its always better than overestimations.

            Btw – whats the twist rate at each of them?

          • I usually assume 1/7. It’d probably be around there for each of them. Maybe 1/9 for the 6.86mm.

  • Mr. Katt

    It is logical to go with the Vulcan solution since, as we all know, the Romulans always lost out to the superior firepower and logic of the Federation . . .

    A three piece sectional projectile for the 5.56x45m/m NATO – It’s logical.

  • Eric Frey

    well, I would start out with the question – what do I want my gun/round to do?
    then, you design the most appropriate balance between kinetic force, accuracy, and recoil.
    good example – the 5.56×45 is easy enough to control, but lacks kinetic force. the 7.62×39 is quite a bit stouter, but recoil is on the edge of being difficult for many people. I’m a big fan of 6.5 SPC because it strikes a balance between the two, although there is plenty of room for improvement.

    • LMG

      So i guess with 6.5SPC you mean necked down 6.8SPC. Pleeeeeenty of room, yes, better start from a clean sheat than using this as startpoint. Or do you mean eighter 6.8SPC or 6.5Grendel? (both are totally unacceptable and are absolutly unoptimized).

      • Big Daddy

        How many people or for that matter animals have you shot with any of them?

        • LMG

          Yeah sure thats the only thing that counts, how many humans did you kill with 6.8SPC. If you prefer 6.8SPC in combat over lets say a .243 CT. Why not just use a god damn stick or just stone…?

          Physics dont change for your tiny brain, like seriously.

          Also 6.5Grendel is a NO GO in military automatic weapons, its case angle is incredible shallow. I did not say that without a reason, there are more than ballistics concidered here.

          Also, for the same muzzle energy, you can make a lighter round, with less recoil, an extreme HIGHER amount of energy at range, with a FAR flatter trajectory and less wind drift. This is the DEFINITION of room for improvement

          Or to put it simply: For the same recoil, you can make a round with far HIGHER kinetic energy (ofcourse way better trajectory and drift too)! = more dead. That should be easier to understand for you.

          • Big Daddy

            So your answer is none. Physics never killed anyone, men on the ground and in the air have and again like so many here y’all discount that over and over again.

          • LMG

            A man pulls the trigger, by a biochemical choice and reaction, muscles react and pull the trigger, the hammer hits the firing pin igniting the primer, the primer ignites the propellant, the propellant burns and creates pressure, the pressure accellerates the bullet, the bullet exits the barrel, air slows down the bullet in flight.

            The .243 NF EPR due to its long MPBR and flat trajectory hits the enemy combatant peaking out with his rifle behind a thick concrete wall at range, it passes trough him, the jacked fragments, its core and penetrator tumbles. His lung collapses, he dies shortly later.

            Even tough he almost hit the bluefor solider the shot before, but his 6.8SPC had to much drop and too short MPBR, so it hit the thick barrier.

            Badum Tss

          • Aono

            You forgot how the 6.8SPC was an M14, so only 9.9/10. Sorry.

            It goes without saying what the 243 is.

          • James Kachman

            Do you understand how that is a non sequitur? We’re discussing what is the realm of physics and engineering; that of design and construction of a technical device. Obviously yes, applying these technical arts outside of their realm is misguided – I would hardly turn to a physics department to lead rifle platoon, amusing though that would be. But to give the man on the ground the best possible technical device, the finest engineered implement of war, truly is the realm of the technical and the engineered. What is it that you think we are discounting, exactly?

          • I don’t think he’s ever read The Land Ironclads. Maybe he should.

          • James Kachman

            Can’t say I’ve read it myself, either, tho Wikipedia suggests it may be a lesson quite needed. (And, well, an argument for the “outdoorsmen” carrying a few weapons named for our favourite Swedish King. :P)

          • The creepy thing about Wells’ story is that it ended up being totally vindicated by experiences in WWI and WWII. 😐

          • Brett baker

            You suggest the possibility he’s fully literate.

          • Be nice.

  • Aono

    What, no graphs? Let’s see graphs with the requirements thresholds, comparing all the rounds.

    • Planning on it for part 2.

      • Aono

        Nice. It would help to illustrate how the Vulcan can proceed in a requirements agnostic way. That’s especially helpful when then putting it in context with other cartridges.

        • Part 2 is going to have an in-depth discussion. Ideally this would have been one big post with everything at once, but then it would probably have been 5,000 words. So I had to break it up. There’s a lot more to say.

  • Some Rabbit

    Vulcans, always gotta do it the hard way. Everybody always wants the magic cartridge: hard hitting, long range, flat trajectory, low recoil and light weight. But many nations decide what bullet diameter they want first and everything follows from there. Italy and Japan had a 6.5mm before deciding they wanted something bigger, Germany always felt comfortable with an 8mm, Spain and Latin America the 7mm and the US, UK and Russia a 7.62, so it seems bullet diameter is more about national identity than ballistic efficiency. I always felt the .243 Win. (6 x 52) would make a great all purpose military rd.

    • ARCNA442

      None of those numbers pulled from a hat because of national preference but reflected the state of art of the era in which they were designed. Germany was “always” comfortable with 8mm because their military was treaty limited between the wars. The UK tried to switch away from 7.62 several times but events and budgets prevented it. The Russians stuck with 7.62 because communists love top down standardization. But none of those calibers are still standard issue and haven’t been for nearly 40-70 years depending on the nation.

      • Well, the Russians (and plenty of other people) still use the 7.62x54R round…

        The Russians ended up with it for much the same reason that the US did — it’s basically .3 inches, a nice round number that falls inside the spectrum of what everyone else was using (yes, the Moisin Nagant was designed around an non-metric round — that’s why it’s called the “Three Line Rifle” – a “line” being 1/10th of an inch.)

        • ARCNA442

          No one uses 7.62×54 as anything but a machinegun/sniper round.

          It must be remembered that the number in a cartridge’s name is only slightly related to the actual bullet diameter. Further, design differences mean that smaller caliber bullets can actually weight more than larger caliber ones. Finally, most of the rounds we are discussing were originally designed for round nosed bullets and later updated with spitzer bullets. All of these factors combine to make a discussion about their nominal caliber less than fruitful.

    • gunsandrockets

      I have to disagree. There was tremendous flux and actual experimentation when the nations of the world choose service rifles before WWI.

      And even with the experience of WWI behind them some of the nations of the world came to quite different conclusions as to the best qualities of ammunition.

      Heck, it’s why such silly caliber debates still generate such heat even now.

    • gunsandrockets

      Much of what nations ended up using in WWII was only because of the tremendous investment those nations made in that caliber during WWI.

      And many of the largest nations of the World were stuck with calibers in WWI that they didn’t want, that they were in the process of discarding when the emergency of WWI was upon them.

  • Brett baker

    When are we getting an article on how we could design a PDW that weighs 3 kilos, has 800 meters range, holds a lot of rounds, but we Can’t get it because of the lobbyists?😉 The worst thing is people think it’s been done.

    • Blake

      You could get pretty close with a .204 cased-telescoped projectile, (if the range was more like half that, which is largely sufficient for a PDW)…

    • Chris Miller

      While not quite meeting your criteria, the Knight’s Armament PDW chambered in 6x35mm seemed to fall victim to what you’re describing. Weapon was 4.5 lbs and the caliber was designed to be effective at 300 meters (appropriate for PDW role).

  • Edeco

    I’d use mathematical optimization, which Mr F is on his way to reinventing. But then someone take my product and screw it up.

  • Brett baker

    Wouldn’t be easier to just set phasers on kill?

    • LCON

      The Borg have adapted to your post. Resistance is Futile.

  • marine6680

    Yay science!

    Also the takeaway I am getting… Moving to the 308/7.62 is a bad idea… Lol

    • Rifle

      Its an unspeakable bad idea actually. So bad its not even anywhere near the maximum here and has an even much worse shape too.

      • marine6680

        Yeah, I know… Thought the idea was pretty ludicrous when I first heard about it.

        Since then it seems a theme of several of Nathaniel’s articles have had an underlying tone of… “Moving to 308 is a horrible idea”

        • Obviously, my feelings on the subject range from hugely skeptical to outright concerned regarding the ICSR announcement. It smells to me.

          Having said that, in US service right now, there are two small arms calibers: The 5.56mm and the 7.62mm. If – and this is a big if, but bear with me – if the 5.56mm is determined to not meet the requirements for near future warfare for some reason, then the only other option that is currently in-service is 7.62mm, however suboptimal it may be.

          This of course entertains the idea that there is some target or job that 7.62mm can do which 5.56mm cannot. And there are some where that is true. For ICSR, the stated gap is with armor penetration, however, and if I’m being perfectly honest I am very skeptical that 7.62mm has any meaningful advantage there. But maybe I am wrong.

          • marine6680

            Isn’t velocity one of the most important factors in penetrating armor?

            5.56 has the advantage there… Seems properly designed ammo would do the job.

          • Yeah, I agree. Even though 5.56mm has more drag, you’d think a decently designed armor penetrator round would do the trick.

    • DW

      It might not be if the requirements change due to various causes (exosuit proliferation, fighting nonhumans, or fighting in space). But the paradigm now strongly favor .224cal and not .308cal for mass issued rifles.

  • Kaban

    In (half-hearted) defense of Romulan engineer: he does have a design process. It is just it is simple, straightforward and amplifies Poor Requirements (the bane of all engineers, fictional or not) by Poor Analysis. Which does him no credit, for sure. Even with “do it yesterday” deadline. I never do like him. Mostly.

    On more serious note, he does have exceedingly poor requirements and design goals. Otherwise, he might actually have to go with more Vulcan-like, possibly iterative (“Let’s see if our boys can really control that thing in short bursts, or you need to go back to drawing board, egghead!”) process. It is damn hard to pick “that’s probably OK solution” and have it meet gazzilions of criterion.

    Have to say I do enjoy your pieces on caliber selection. They bring in a perspective that is, sadly, lack in so many heated arguments that boil down to “Dammit, rebarrel it to Grendel/6.8 SPC and we are golden”.

    • Absolutely, the preference-driven design method has advantages. I will get more into it tomorrow, but for one thing it is a lot quicker, and requires substantially fewer resources to do. For another, in certain situations it can actually produce better results because it’s intuitive.

      • Ballistic

        If you can calculate that for a SINGLE article. Than payd engineers just using the preference method for military ammunition later costing millions, are eighter unbelievable lazy or dont know at all what theyr doing.

        • DW

          But we do need Romulans’ experience to set a good set of criteria for Vulcans to work with.

          • 100% agreed. Setting good requirements is the key here. I think a lot of questions like “what do you want?” should be replaced with “what do you need to do?” Let the engineers do the actual engineering, it’s what they’re good at. Let the soldiers tell you how they need to fight.

          • noob

            Based on the trend at the highest levels of government, I feel like the politicians would like to fight in a way totally alien to what we do now:

            1) use big data to identify behavioral signatures of possible threats
            2) mass surveillance to confirm existence of a threat
            3) disposition matrix to, uh, “dispose” of the threat.

            Right now 3 involves a predator drone, especially if you’re a Jonas Brother trying to date Obama’s daughter, but in the future imagine this:

            3) disposition matrix assigns threat to “automated rendition” –
            4) Automated rendition system activates. The subject enters their driverless car and asks to go to the hardware store to buy some nails and fertiliser for his “farm”. Instead the doors lock and the car drives him to the airport. He is never seen again – his transit history says that his car arrived at the hardware store and surveillance footage shows that he then decided to go for a walk into a camera blind spot and never emerged.

            None of our guys were at risk (we pumped anesthetic gas into the locked car before opening it). Not a shot was fired.

            Until the subject arrives at their destination, they don’t even know they’re under surveillance.

        • Many is the design meeting I have sat through, where the engineers were saying, “This is a better solution to meet your actual performance requirements,” and the brass saying, “Don’t care. Bad doggy – no biscuit! We want ‘X’. Happy with ‘X’. Make ‘X’ work.”

    • LCON

      I am sorry you cannot say “Dammit” in a Star trek Referenced Article , Unless it includes “Jim I am a Doctor not a [Blank to be filled]”

  • Sid Collins

    Okay, so how soon can I purchase an AR in 6.86x46mm Romulan?

    • Rifle

      Hopefully never.

    • Brett baker

      As The Great Satan, we need a 6.66 cartridge.

    • DW

      You get a 6.8spc AR and somehow handload EPR bullets and more powerful charge in it. And undergas it so it doesn’t go KB on the first mag.

  • Joel

    Is minimum fragmentation speed caliber independent?

    • I am not sure, there’s not enough public testing to say. The physics suggest it is, but this obviously depends on the particular design. What we do know is that 1,900 ft/s is verified for M80A1, and there’s some evidence to suggest that M855A1 fragments at least that low. So if it isn’t caliber independent, it is probably lower for smaller calibers.

      However, for the purposes of demonstrating a process as I am doing in this article, a fixed value is fine.

  • Carl Mumpower

    Nicely done – interesting and creative. Thank-you!

  • James Kachman

    Another sterling article, thank you for your work!

  • Raoul O’Shaughnessy

    “Explicate”? Explicit, maybe……

    • “Explicate” is the verb form of “explicit”.

  • Henry Reed

    Nathaniel, this is truly amazing work. All hail the M855A1, I guess? So we’ve seriously reached the pinnacle of ballistic capabilities for military small arms?

    • Units

      Are you kidding did you only looked at the diameter? Projectile shape, ballistic coefficient, velocity, muzzle energy are way diffrent.

      Also its a bottleneck case so the “pinnacle” is out of sight for it.

      • Henry Reed

        So you’re saying that no 5.56 load matches that criteria yet? What’s stopping someone from making it?

        • Units

          Exactly due to the diffrent COAL, it would not fit in the magazin nor magwell.

          Not worth to adopt a bottleneck round. As well as massive lobbyism and the biggest problem currently most engineers are romulan (preference based), so the rounds they present for adoption are highly unoptimized and just flat out bad.

    • Thank you for the kind words. Couple of things to keep in mind: First, this study isn’t intended to point towards “the best” round. Many of the metrics I use are placeholders (they are pretty good ones, but still), if this eval was done “for real” I would expect it to use finite element analysis to select the ideal fragmentation and penetration characteristics, and then verify that with empirical testing. That could very well lead to a different result than what is shown here. Also, this study’s requirements are just placeholders as well. This is really about comparing the different processes against each other, not about saying “.224 Vulcan is the bestest round of all time”. I don’t think that’s for me to decide, anyway.

      Second, the .224 Vulcan is substantially ballistically different than M855A1, despite sharing the same construction and projectile diameter. The most important difference is that the Vulcan has a much higher ballistic coefficient – 0.211 G7 vs. ~0.152 G7. This means it retains energy much better than M855A1, while also starting with ~15% more. M855A1 could not meet the “Vulcan’s” requirements, which I don’t say to suggest that makes it a poor round. Still, the two rounds are quite different.

      • Henry Reed

        Someone just needs to make a rifle and magazine to accommodate the Vulcan’s specs, preferably in an AR-style platform, and we have a winner.

  • Rick O’Shay

    This is some fantastic Saturday afternoon reading.

  • A.J. Hodges

    Preference driven design is a great way to run a company that sells primarily to civilian consumers. R+D is cheaper than with process driven design and it doesn’t matter if it’s actually better if your marketing department can get people to buy it. Know anyone with a brand preference or any trend followers? Those are your customers.

    On the other hand those who make for military and law enforcement SHOULD use process driven design. Since very few of the people who make decisions for military and law enforcement have heard these terms let alone understand them it is doubtful that is the case. If you want to get a half a billion dollar contract you have to give the customer what they want, regardless of how stupid they or their requests might be. Not to say that those running MHS were stupid, but they cannot afford to be Vulcan as long as they are overseen by a Congress filled with politicians.

    • Preference-driven design is also a great way to make art, for example. I am not trying to say that one is “better” or “worse”, but I do think if you’re going to make a logistical commitment that is likely to stick with your for 40 years or more than process-driven design makes a lot more sense.

      • noob

        Oh i just realised. What if all the stuff Disney is doing lately is Process Driven Design creating a spectrum of art products fot maximum profit. this is horrifying.

        • That would be funny AF.

        • Kaban

          I am afraid your joke is not joke at all, and it is precisely what top brass of Mickey Empire do.

          – Re-evaluate status and popularity of owned franchises.

          – Conduct same study of rival franchises: box-office, critical consensus, merchandise, rent, etc.

          – Predict political “do and don’t” guidelines for lifecycle.

          – Set up goals in terms of box-office, merchandise, etc.

          – Evaluate a variety of projects, by drawing from current pool of propositions and by tasking teams to produce new propositions.

          – Evaluate its proposition’s revenue by playing with its parameters. Bloated cast for more variety of HappyMeal toys, or smaller cast, but more expensive toys?

          – Etc., etc., etc.

          Okay, I’ve ass-pulled this example, but I suspect something similar happens in reality 🙂

          • noob

            And all this time we thought vulcan art was weird sculptures made of red clay. It turns out it is more like Pirates of The Caribbean.

        • Edeco

          Disney employs a lot of people with degrees for this kind of thing.

  • Blake

    We all know the Vulcan solution won because he used the metric system…

  • Blake

    Thanks for including the .204 in this study, it’s an underappreciated caliber.

    Do you think that e.g. a 62gr boat-tail bullet in that caliber would have less of the “barrel burner” problem than the selected 50gr projectile?

    • EPR

      Now how do you put in 62gr in .204 …. In EPR density limits. Its twist rate would rip appart its jacked. Also its 5.01 not 50 grains.

    • It would burn barrels less because it would retain energy much better, but the projectile would have to be exceptionally long, nearly 6 calibers. This would make stabilization a problem, and it’s not clear it could be solved.

      • Blake

        Yep, according to Berger’s stability calculator it would pretty much require a 1 in 6.5″ twist or better.

        I’d be very curious to see the results of this setup, along with “superformance” powder, which is very close to 4831 but sustains a longer “peak”…

        • An EPR is 10-15% less dense than a lead cored OTM, so it would have to be considerably longer.

        • Stability

          Do NOT use berger! Its useless. Its purely based on length, diameter and density.

          Nose ogive lenght, nose ogive shape, bearing lenght, boattail lenght, boattail degree, meplat size, etc etc do all play an enormous part in stability.

  • TJbrena

    Sisko>Kirk>Picard>Archer=Janeway

    DS9 is best Trek.

  • I tried to read this article but instead got into a deep conversation with Nathaniel about Star Trek and its foibles.

  • iksnilol

    what does 40mm grenades count as?

    • Blake

      Klingon 🙂

      • LCON

        No Klingons Adopted 7.62x39mm with fixed bayonets on all there weapons. so if the rounds don’t kill you The blades will Skewer you and if the blades don’t kill you there breath sure as hell will.

        • “SCHV cartridges are suitable only for shooting Tribbles!”

        • Side mounted bayonets so you can have rifle AND grenade launcher…

  • Nunya Bidniz

    Actually, you’ve left out one of the criteria that no self-respecting Vulcan engineer would overlook: since capillarity only evinces in barrel diameters below .250″, that would act as the basement for caliber considerations since soldiers will inevitably end up needing to fight in the rain, slog thru swamps, crawl out of the sea onto a beach, etc., notwithstanding Vulcan being a desert world… Tsk tsk!

    • There is considerable evidence to suggest that the famous AR-15 rain tests were a sham. Perhaps the biggest evidence for this is that the US, USSR/RF, PRC, and NATO have all been using bores smaller than .25 caliber for several decades now with no such ill effects.

      • To be fair, both the ArmaLite and Winchester rifles suffered burst barrels in the rain tests. They were each trying to shave off as much weight as possible to meet the CONARC requirement. The issue pretty much went away after each beefed up their individual barrel profiles. You’ll note that one commentator in the Army’s reports pointed out that the rain tests could even bulge larger caliber barrels if they were not drained properly.

        Besides George Sullivan’s bungie-cord management style, ArmaLite also had a questionable history of attempting to directly scale down parts from Stoner’s 7.62mm designs for their .222/.223 prototypes without taking into account whether the smaller dimensions were adequate. For example, note how many of their prototype SCHV designs suffered from wrecked barrel extensions that were too small: the AR11, the pre-AR15 attempt at a scaled-down AR10, and the pre-production AR18.

    • Kaban

      Once or twice I’ve come across the claims that Soviet pre 5.45×39 studies determined threshold to be somewhat under 5mm, i.e. slightly less that .200, and that the 4.5mm (.177) barrel is dangerously likely to retain enough water for KB, even after weapon is given smart shake. However, I did not pursue the source, and the numbers might be way off. As Nathaniel pointed out, there is ample evidence of .223 barrel to be acceptable in this regard.

  • Ryfyle

    I wish you could stay consistant in your measurement systems. Blending up empirical and metric just add a ton more math in the conversions. Doesn’t Star Trek use some sort of magical particle for all their energy weapons? Make more sense just to stick with slugs.

    • I’ve been working in both systems simultaneously for so long that it just comes naturally to me now. In this case, by the time I had finished all the calculations I realized they were in a mess of different units and that correcting that would be fairly painstaking. So I left it, and put an apology in the tags. 🙂

      Another problem is which set of units to use? Full metric would work, but I would be speaking greek to the people who use Imperial. I feel it is important to have some data in Imperial, like velocity, as that is understood by Americans and Europeans alike (the foot/second is still often used as a unit of art in firearms in Europe). But oh god, I do not like working in full Imperial, it’s a mess. So instead I just offer my apologies – though it’s especially bad in this case because the units aren’t even necessarily the same across all of the same quantities!

  • nadnerbus

    I know your process criteria is more for demonstration purposes, but another factor to consider is portability and controlability for the 5 to 95 percentile soldier. An optimized round and weapon is far less useful if a large portion of your forces can’t employ it effectively.

    • luck

      Luckly the nearly most portable and controllable was in the other sweetspots already. And as he noted, for reaching the requirements it also saved a ton of weight.

  • zombietimeshare

    How would these rounds do against a phased plasma rifle in a 40 watt range?

  • Ark

    Cartridge design is really just one big exercise in trade-offs. The real revolution will either be in case materials (or caseless) or some sci-fi operating system like magnetic acceleration. Until then, there really isn’t much reason to move away from 5.56 as the general infantry rifle caliber and a handful of other calibers for more specific roles. Otherwise you’ll just get stuck in this back-and-forth loop of making and then undoing trade-offs.

  • kyphe

    For some inexplicable reason the .277 Romulan reminds me of the .276 Enfield and the narrowly avoided disaster that would have been the pattern 1913, if WW1 hadn’t started early enough that the Lee Enfield was still in standard service and we still had huge stockpiles of 303.

    Both the round and the rifle were preference driven designs with procedural tweaking. Committees given the task of investigating all the best qualities of current firearms around the world to decide what to copy based on the experience of fighting the Boer war. But the perfect rifle for fighting irregulars in south Africa was not the perfect rifle for the trenches of western Europe.

    Just as the M4 may be perfect for urban Baghdad but less so for the Arghandab River Valley.

    • The 6.86x46mm Romulan is at least a little more reasonable than .276 Enfield. That round off the top of my head pushed a 165gr AP pill at about 2,800 ft/s. Yeesh!

  • Blake

    Interesting how the selected .224 case is almost identical to 6.8SPC’s case…

    • It’s actually a lengthened 5.45mm case with different extractor groove dimensions.

      • Blake

        очень интересно

  • Glad!

  • “You might want to check Daniel Watters timeline again.
    June, 1965: “Aberdeen’s D&PS publishes the report ‘Engineering Test of Cartridge, 5.56-MM, Tracer, XM196.’ The purpose of the test was to determine the XM196’s physical dimensions, accuracy, tracer performance, cook-off temperature, vibration effects, brush deflection, erosion, penetration (pine board, steel helmet, and armored vest), and gun functioning. It is recommended that the XM196 be considered suitable for use with the M16 and XM16E1 rifles.””

    You might want to read HWS III, which makes it clear that .223 tracer development was ongoing in late 1962, and XM196 was type classified on October 23, 1963. The very first prototypes of the Stoner 63 were made only earlier that year. The Stoner 63A didn’t reach production until 1966. So where was the machine gun in 1962?

    “M16 is a tracer/incendiary. But keep trying.”

    You might want to read HWS II, as well:

    http://i.imgur.com/USEQF7C.jpg

    “I love that I have to hold your hand through this.”

    What happened to your concern for “character”? Seems to have mysteriously vanished.

    “So here’s the point: there were other solutions they could and should have pursued to increase the performance of the AP rather then make the case larger.”

    Oh? Such as? Increasing the velocity? That requires more case capacity. Using a longer penetrator? That requires more case capacity.

    “The Swedes figured it out, and the U.S. finally did also in 1992 with the M993 & M995.”

    You appear to have missed the bit where they already tried a tungsten penetrator and it gave 3/5ths the performance of .30 cal steel core.

    “And I care, it’s as much my business to evaluate their decisions and publicly criticize them as mistakes in this as it is anyone’s to defend it. Same as I will critize present day ordnance mistakes (like switching to a 7.62mm from 5.56mm), whether my opinion on the matter is listened to or not.”

    Whatever floats your boat.

    “There’s no need for passion there.”

    You seemed pretty passionate about the other stuff.

    “I believe you’ve pointed out yourself in a past critique of the Garand, about how the dogleg arm that raises the follower in the magazine is prone to being bent and causing premature clip ejection already with just the 8-round load, this would only be exasperated by increasing it’s length to handle a taller clip and heavier cartridge load.”

    You wouldn’t have to increase the length of the arm to do that. Go look at how a Garand works.

    • FWIW: XM196 was still a test item in 1963 and not yet approved for issue.

      Here are a few early snippets from my unreleased update for the 5.56mm Timeline.

      November 1963: Frankford Arsenal has been instructed to proceed with their ammunition development program, which includes tracer, blank, dummy, and HPT.

      February 1964: Frankford Arsenal draws up specifications for the XM196 Tracer.

      July 1964: The TECOM Action Officer for the Engineering Test/Service Test (ET/ST) of XM196 Tracer ammunition informs LTC Yount that the results will be delayed from the end of the month to the end of September. The XM196 ET has been delayed due to the current schedule of SPIW tests, the M16 Comparison Test, and the AR-18 Military Potential Test. As this setback will delay standardization and procurement for urgent overseas requirements, Yount considers requesting a Limited Production (LP) type classification for the first 3.5 million rounds of XM196 Tracer.

      The FY 1965 Army requirement for XM196 Tracer is established as 10 million rounds.

      August 1964: MUCOM issues a request to the AMC for LP classification for the full amount of XM196 Tracer for FY 1965. MUCOM’s request is processed and hand carried to the OCRD. DCSLOG LTG Lawrence J. Lincoln, Jr.’s initial reaction is to allow LP type classification for only enough XM196 to satisfy overseas requirements.

      The OCRD approves the LP type classification for 3.5 million rounds of XM196 Tracer.

      Frankford Arsenal issues IFB for production of XM196.

      A delay is granted for the submission of bids for XM196 Tracer
      production. First production deliveries are still required for March
      1965.

      September 1964: Frankford Arsenal receives bids on 3.5 million rounds of XM196 Tracer.

      The USAIB publishes the report “Service Test of Cartridge, Tracer, 5.56MM, XM196.”

      One lot of Remington-produced XM196 Tracer fails the waterproofing test. Frankford Arsenal engineers study the problem. Bids are still being evaluated for the 3.5 million rounds of XM196.

      October 1964: The lot of Remington XM196 Tracer that failed waterproofing tests is accepted. The lot will be restricted to Airborne units and is not to be placed in long-term storage. Temperate zone ET/ST of XM196 is expected to be completed within the month, with type classification predicted to follow by January 1965.

      Olin files a protest with the US Comptroller General regarding the
      contract to Remington for 3.5 million rounds of XM196 Tracer.
      Frankford Arsenal had declared Olin’s bid as non-responsive due to
      Olin’s plan for the free use of government tooling. The protest is forwarded to Secretary of the Army Ailes and is then passed down to the AMC and MUCOM for comment. MUCOM’s response is due to the AMC at the beginning of December.

      December, 1964: A request is forwarded to the AMC Technical Committee for the type classification of XM196 Tracer as ‘Standard A’ for temperate use only. Arctic testing is scheduled for winter.

      MUCOM’s response to Olin’s protest of the XM196 Tracer award is forwarded by the AMC to the US Comptroller General.

      Remington requests and receives permission for accelerated deliveries of the 3.5 million rounds of XM196 Tracer.

      January 1965: The M196 Tracer is type classified as ‘Standard A’ for temperate zone use.

      April 1965: LTC Yount receives a program for the acquisition of 33 million rounds of M196 Tracer.

      Frankford Arsenal releases an IFB for 37 million rounds of M196 Tracer. Olin is reportedly the low bidder at $57.50 per thousand. The previous contract price was $99.85 per thousand.

      Ammunition requirements for the SAWS program are definitized and are outlined to MUCOM and ASPA representatives. A major problem will be the initial lack of M196 Tracer to meet both overseas and SAWS program requirements. The AMC Materiel Readiness Directorate is asked to approve a temporary diversion of a portion of the overseas requirement. General Besson directs that the M196 Tracer not be diverted from shipments to Vietnam.

      • “FWIW: XM196 was still a test item in 1963 and not yet approved for issue.”

        Absolutely. What I’m pointing out is that development of tracers began before any machine guns in 5.56mm were produced even in prototype form. There could be many reasons for this, naturally (using the M16 as an automatic rifle, for one), but it’s a reasonable supporting argument for an overall point that even if a round is only intended to be used in semiautomatic rifles, it still generally needs a tracer load.

    • ostiariusalpha

      “You wouldn’t have to increase the length of the arm to do that. Go look at how a Garand works.”
      Whoa now, we can argue back and forth about that other stuff, but who are you trying to bulls–t here with this? I know exactly how a Garand works, and so should you, so your claim that the follower arm (this thing https://uploads.disquscdn.com/images/4bfeb6f5ecdef33f491ac02f0feef48cf4cb8c6fd368850f75da495dd7f066ba.jpg) wouldn’t have to be longer is pure dumbassery.

  • It is noteworthy that ammunition engineers from three different decades thought tracers were necessary for semiautomatic rifles:

    http://i.imgur.com/DNVXY1s.jpg

  • gregge

    Meanwhile, a Vulcan engineer has also been tasked with designing a 600 meter small arms round.

    The Vulcan rejects the task with the statement “Vulcans rely on peaceful diplomacy. We do not design weaponry.”

  • Richard Lutz

    7.62×39 rules!
    Surely the 7.62x39mm round rules for use in an assault rifle, while the 7.62x54R is ideal for use in belt fed machineguns due to its rimmed round, and can be used in DMR rifles like the SVD, while the .338 LM is ideal for long range sniper rifles.

    • DMR

      Exept that 7.62×39 drops like a stone, has an hilarious low supersonic range for supression, has a ton of winddrift. And is so thick that its KE/mm² (steel penetration) is garbage. Also its FMJ’s icepick, so its terminal performance is verry unreliable. And it even weights more than comperable better rounds.

      7.62x54r has a totally stupid shape that makes it incredible inefficient for its high weight and recoil.

  • 3756

    the 224 vulcan sounds too good to be true. How could it perform as calculated from a 16 inch barrel without excessive muzzle flash, noise, recoil? look at the grendel. it seems to only do good (for military applications) out of a 24 inch barrel. but then, whats thu use of that, if everyone wants to have a 16, 14 or even 11 or 8 inch rifle?
    yeah, muzzle devices, but then you deafen your buddies next to you.

    And what about pressure? Ive tried to understand the powley computer before. why does it read 69000 psi (excessive) and right above 56000 cup? and why does it say 2750 fps in the middle column and something like 2400 fps in the left one?

    • Johannes von’ Strauch

      The 690000psi is not the actual pressure, the calculator uses IMR powder, so he uses a verry good modifier that simulates the better SMP-842. Which would have normal pressure.

      Also no its not too good to be true, actually the faster rounds have a greater advantage over the slow than shown here due to the lower drag at high velocitys, this could be even further increased by using an velocity-optimized shape for the faster ones. Also it has a thinner diameter so much less frontal area, therefore it can penetrate with less energy.

      The Grendel is too slow, and has the terrible lenght limit of a AR15 Magwell COAL. You see here how much energy and what a large case the .264 requires (2731Joule), the Grendel is unable to provide that, and has its projectile seated much deeper, that takes up a lot of volume and reduces velocity for a given save pressure a lot.

      For the .224 Vulcan, if someone wants to use a shorter barrel, the added +250fps over the requirement will do a verry good job of balancing it out, also i dont think someone would expect 600m from a 8″ barrel SBR, and it doesnt mean at all he cant hit at that range anymore, just with less performance and more drop, and still a lethal wound depending on where it strikes.

      Also PSI=Pounds per square inch, while CUP=Copper units of pressure, using a copper crusher.

      • 37566

        Yeah, what i mean by too good to be true is, if the 224 vulcan would perform as calculated here in the real world. I mean muzzle velocity from the given barrel length, internal ballistics.
        Is IMR really that terrible compared to SMP? Or: is SMP so expensive that it wouldnt be the obvious solution to the military’s problem of too small lethality (velocity) out of the given barrel length? maybe they could have kept M855 and instead invested their EPR money in a differnt powder. just sayin.

  • Will

    Super interesting article. To be honest, I’d like an AR chambered in 6.8 Romulan. Just to show off at the range. You can imagine the looks you’d get when you mention the caliber. And that bullet design is awesome.

  • James Kachman

    Hello Nathaniel,

    I know this may be buried, but any chance you could share which Ballistics Calculator you’re using? Trying to do a similar project where I establish a BC and needed velocity @ needed range, then establish the muzzle velocity, but I can’t find the equations to do it.

    Thanks in advance!

    • Johannes von’ Strauch

      No problem, ive seen it pop up. Just search for JMB or jbmballistics.
      Click on Trajectory for the aerodynamic calculations. And the internal ballistics calculator is Powley.

      But dont assume the aerodynamic outputs are absolute accurate. BC varies with velocity. Therefore you might greatly overestimate energy at range. So using a Form Factor or BC of an existing projectile is verry risky if you dont know the velocity its fired at and for what range the bc then is meant for.

      If you need any further information no matter how technically complicated, or help, im always open for ballistic questions.
      Over E-Mail, Google+, or if wanted Skype.

      What youre working on, Rifle ammunition i assume?

      • James Kachman

        Thank you for your response!
        I found the JBM, but it seems to work beginning from an established muzzle velocity. It’s not helpful in determining the muzzle velocity needed to, say, achieve a 1900 fps threshold at 300m, which is the math I’m trying to do.

        From what reading I was able to find (talking to *shudder* mathematicians) it appears G7 BC is fairly accurate above a threshold easily met within the supersonic regime. Further, this is simply a thought experiment on the internet, something akin to “how small could we scale down 5.56” and so extreme precision isn’t required.

        And yes, it’s rifle ammunition, albeit bleeding into the PDW catagory.

        • Johannes von’ Strauch

          Ok PDW’s to be honest are outside of my intrests. I designed serval high end versions and the ammunition, but i have no time for that area now due to the extensive work and time on Rifle ammunition, i might pick it up later.
          I really wondered first why in the heck 1900fps at 300m, but in the case of a PDW yes it makes sence.

          Think about a few things when scaling down your ammo –
          1. Use an aerodynamic projectile shape to reach minimum weight and recoil while still have the required energy/velocity at range, this means not using the short nose ogive of 5.56×45.

          2. Be carefull with scaling down projectiles, stability might greatly suffer due to the thin diameter and therefore reduced gyroscopic stabilisation.

          3. Calculate with Powley the internal ballistics to not overestimate the round, use sencefull pressure (55000-62000psi), with the powder charge output you also can calculate recoil, and with the case capacity the round size/ magazin capacity. Or if the cartridge size is given the possible muzzle velocity.

          4. Remember to have good stability even in bad atmospheric conditions like low humidity and cold weather. If you dont count that in your Projectile will be highly unstable in cold or dry conditions.

          Have fun, good luck.