Incredible High Speed Footage Of The Army’s New Round In Gel

If you had any doubt at all about the terminal performance of the U.S. Army’s new M855A1 Enhanced Performance Round before, prepare yourself. YouTube ammo tester The Wound Channel has partnered with Aimed Research, who is providing the cameras needed to take ultra-high-speed video of bullets in flight. See the video below of the M855A1 EPR doing its thing to a block of Clear Ballistics gel under the watchful eye of a Phantom high speed camera:

Needless to say, the M855A1 round gives exceptional performance in gelatin for a round of this size – exactly what we’d expect from a round that was the result of one of the most extensive small arms ballistics research programs in recent memory. The Enhanced Performance Round offers the incredibly short neck that ballisticians have been chasing for decades now, while retaining excellent penetration due to its “arrowhead” penetrator and copper slug. A wide terminal cavity is given by the resulting immediate fragmentation and deposition of energy into the block, which then collapses back in on itself. This creates one of the strangest phenomena I’ve ever seen in gel: A secondary temporary cavity caused by a fuel-air ignition. William and I discussed what may be happening here; his thoughts are below:

The flash/explosion in the gel hasn’t been very well explained so far. The best explanation I have is that the hot bullet vaporizes some of the gel (which is flammable) and between the friction, heat of the bullet, and air being sucked into the temporary stretch cavity, as the TSX collapses it acts like a diesel engine and compresses the mixture of heated gel vapor and air until it explodes. You can see the exhaust gas exiting the entrance hole. I don’t think that the air can be pushed out as fast as it is sucked in, and without a place to escape the pressure inside that bubble is tremendous as it collapses. Some people mistakenly identify this as sonoluminescence, but that is just a flash of light not an actual explosion/burning. …That phenomena would not happen in tissue, I don’t think.

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


  • Yimmy

    First!!! FUAROCK!!

  • TheSmellofNapalm

    Absolutely beautiful. Is this round going to be available to civilians any time soon? Who makes it and what is the construction?

    • BattleshipGrey

      I can’t quite say about availability. IF we get the chance to buy it, it’ll probably take a while for the quotas to be met and then the over-runs will hit the civilian market… Or, they could just say “no, you peasants can’t have this particular instrument of death”.

      Found the below chart for the construction.

      • The round is currently classified the same as M855 legally, and a handful of rounds have made their way into private hands (including mine). However, the Armt is trying to build up their stocks of A1 ammo right now, so we won’t see major surplus for a while.

    • ostiariusalpha

      Considering that Liberty Ammunition actually owns the patent on the M855A1’s design, you might see it from a civilian ammo manufacturer some time before any overflow from a military contract is available.

      • My strong suspicion is that LA is basically a patent troll group that got lucky. If that’s the case, then the Army shouldn’t have to give them a cent.

        I admit I haven’t really kept up with the status of that lawsuit, though my understanding is that the case is ongoing in one form or another.

        • ostiariusalpha

          No, Liberty actually sells their multiple boutique rounds. In fact, they sell the M855A1 type round as the Liberty National Defender 5.56. Good luck trying to get ahold of it for now if your not LE/Mil though. The government apparently didn’t appeal the $15.6 million verdict, so the legal wrangling seems to be over.

          • I know they actually sell them, but if you look at their patents, it looks like they’ve patented essentially as many random different bullet configurations as possible. That, and I do not buy their narrative that the Army tested their round first, which led to M855A1. The Army may have tested their round, but the M855A1 program was far too extensive to marry nicely with a narrative of government theft. Why put so much effort into research if LA just handed you exactly what you want?

            This, added to the fact that apparently the secret sauce of M855A1 has much more to do with CoG placement, ratios of the masses of the different components, and details of their design (none of which the LA round apparently duplicates) than it being just three parts leads me to believe that LA is just trying to get their slice of pork.

          • ostiariusalpha

            Heh, this kind of puts me in the position of defending Liberty Ammunition, which is odd for me since I’ve never been all that impressed with most of their designs, but the heck with it. The way I see it, as long as Liberty is trying to develop and market real ammunition based on those multitude of patents (and, importantly, can defend the patents in court as innovations), I find nothing wrong with them pumping out the patents as fast as possible. They did develop the tripartite construction that is key to the M855A1, even if the resulting bullet has refinements that are not entirely identical to the original design. There were certainly refinements produced to bored-through revolver cylinders that still violated Colt’s patent, and they were legitimately sued for it. As far as how much more effective these supposed refinements are in actual terminal performance, it would be incredibly enlightening for someone like the Wound Channel to get ahold of some National Defender rounds and put them up head-to-head with the M855A1 against a variety of materials (denim layers, glass, sheet metal, etc.) and see how different they really perform.

          • The LA bullet is not, so far as I am aware, the “original design”. That is a line maintained by LA, but it sounds too convenient to me.

            My immediate reaction to LA’s patents was “oh, this is just like the stick patent”; they’re way too generic and appear designed primarily to cover as wide a base as possible – exactly what I’d expect from a patent troll.

            Maybe LA really believes in their ammunition, but it seems highly unlikely to me that their narrative (that they showed off their design to the Army, the Army rejected it, and then sneakily copied it as M855A1 because it was so good) accurately reflects reality. This, by itself, is indicative of either some dishonesty or remarkable blindness on the part of LA, that they are unable to recognize a parallel development like that of M855A1.

            Further, it’s silly to me that something that was the result of a tremendous amount of research and engineering, like M855A1, should be held as a copy of LA’s bullet designs, which exist in plethora as the result of mere “shotgun”-approach to design. I guess I might not be giving LA enough credit here, but that’s what my spidey sense is telling me, anyway.

          • ostiariusalpha

            Ha ha! Well, be that as it may, they were able to present enough evidence in court that development of the M855A1 as a tripartite construction only occurred after the same ordnance officers were shown the LA design to win their case with no appeal from the government. It is what it is, I guess.

          • Go back and look at the camoflage competitions that resulted in UCP and the later “Multican under a different name” patterns, and tell me again what lengths the military won’t go through to avoid paying licensing fees… πŸ˜‰

    • uisconfruzed

      You can get a few if you have friends in green.

  • jeff k

    cool but im just not a fan of copper slugs. they make the round cost more and they dont compress or flatten the same as lead.

    • Laserbait

      If M855A1 reliably performs like what is shown above, I don’t care if it doesn’t mushroom.

    • iksnilol

      It literally created an explosion inside the target and you are complaining that it doesn’t compress or flatten?


      • Sam P

        Somehow I suspect that secondary ignition won’t happen in a less flammable material.

        • iksnilol

          Shush now, this is amazing marketing material.

    • The Wound Channel

      This round costs 5 cents more to make than green tip. Well worth it, plus it’s “green”!!

      • Yeah. It’s “green” so they could use the money earmarked for environmentally friendly ammo to do this project. πŸ˜€

        Plus, the Army *does* have a legitimate interest in “green” projos. Not for warfighting, but to avoid turning rifle ranges (normally National Guard, especially long established or indoor ranges) into Superfund sites.

        (Seriously, its a big legal hassle. And the reason why NG armories have those “locker rooms” with big bullet catchers at one end – the EPA made them shut down as ranges, due to fears of airborne lead. HUGE impact on training budgets for NG and Reserve units….)

  • Joe

    This is a great example of advancing cartridge technology. Glad I can take some of this information and show my dad that the M16 he passed up in favor of an M14 and M79 finally has superior terminal effect. As far as expense, you get what you pay for, and the effectiveness in this case is worth it IMO.

    • TechnoTriticale

      re: … the M16 … finally has superior terminal effect.

      And only took just over half a century to get there. Fairly prompt by DOD standards.

      I suspect this is going to further cement Nathaniel’s argument that we’re unlikely to see a new intermediate cartridge adopted any time soon.

      • Kivaari

        An issue, is too many people think a bullet 5.5mm in diameter is inferior to one that is 6mm in diameter. Considering a 5.5mm bullet through a liver creates a nasty wound, it doesn’t matter if it is 0.5mm smaller than the new-exciting-wonderful-magic bullet in another unneeded caliber.

        • Michael Valera

          It’s been shown many times, that where you hit a target is much more important that what you are hitting it with (within reason… I’m talking 5.56mm vs 6.5mm or 9mm vs .45 ACP, not 5.56mm vs .50 bmg).

          • Kivaari

            It’s the old truism. “Only good hits count”. Bullet construction limits performance, especially with handgun bullets.

        • The advantage of the 6-7mm bore size is more a matter of getting heavier bullets without stupidly long for caliber projos that cut too deeply into case capacity and increase overall length to the point you lose too.muh velocity. More energy retention for longer range effectiveness, without sacrificing the advantages of a high velocity, flat shooting, low recoil, cartridge.

          • Kivaari

            I know that. I was inclined towards the 6.5mm bore size 30 years ago. As mentioned here months ago, I had been using the 6.5mm Carcano and it was obvious that the cartridge was nearly ideal, if only a good bullet was used. No long and round nosed projectiles in anything was good. Take those 160 gr. FMJRN and replace them with a lighter and shorter spritzer with or without a boattail. Put a fiber or aluminum insert in the nose (like Britain in the .303 MkVII and Italy did in the 7.35mm) and it would perform better than the 6.8mm SPC. Having 7mm more case length would have been a good thing. That said, a 5.56mm with a good bullet, does the job.

          • jcitizen

            I think Colonel Hatcher said it best when it came to selecting a bullet of between 6 and 6.5 mm. I’m thinking he invented the measurement of cross sectional density and the effect on a target. He always advocated for that range, but no army but the Japanese fully adopted it, and they promptly dropped it in WW2.

          • Kivaari

            I’m not sure what you mean by “…no army but the Japanese…”. The 6.5×50-51-52-53-54-55… etc, cartridges were wide spread from 1890 into the post Korean war period. Most of European armies used a Mannlicher inspired rifle, magazine or cartridge. Many of them were simply the same as the Carcano casing (not the .268 diameter bullet Italy used, but .264) having a shorter or longer neck. A few used a semi-rimmed case. Most European armies excluding Germany, France, Spain and Italy used a 6.5mm. The “best” of that era being the 6.5x55mm Swede. Those using an intermediate case of the Mannlichers used the more primitive FMJRN bullets in the 160-165 grain weights. The bullets were simply too stable. My point being any of those smaller diameter cases (essentially the same as the 7.62x39mm) with a good bullet would have been the “ideal” caliber. Except a you surely have noticed, once the ideal load is found, the search is on to the next ideal load.

          • jcitizen

            Forgot about the Carcano! Thanks for the correction – interesting history! Did you mean to say the bullets were simply too unstable? Many of them were so long and the chemistry of the propellant and misunderstanding of the physics in rifling probably condemned many of them to failure.

          • Kivaari

            Not unstable. In fact the problem with all the early small bore projectiles in military use were long, heavy and round nosed. Those bullets were very stable. Therein was the reason they were poor killers. Circa 1900 an Italian surgeon did a study on the Carcano and found it penetrated and perforated without leaving much tissue damage. Unless bone were struck the wounds were often easily treated, with a soldier returning to the field in 2 weeks. A lug shot or muscle hit would normally heal fast – in a pre-antibiotic era. Irrigation and fresh bandages did work. In the late ’80s, Dr. Fackler while at the wound ballistics research lab in SF, used modern science to verify if the Italian doctor knew his stuff. It turns out the Italian was accurate, and his research was duplicated in ordnance gel. Fackler sent me a letter and a wound track image, saying the 6.5 was the deepest penetrating bullet the US Army had used. He did not have material on the .30 US (.30-40) or .30-03 (not ’06). Those like the early European armies we used long heavy round nosed slugs. The correction was quickly discovered and most, not all nations switched to a spritzer-pointed slug. Britain even went farther with the Mk VII. They inserted a fiber or aluminum nose insert, further shifting the center-of-gravity rearward. So, upon hitting flesh the bullet tumbled and wounds became even uglier. Italy tried it with the 7.35mm round, and it would perform better. Italy just tried to do it in 1938 and the war pressure made the change a bad choice. Had they simply switched to a pointed-flat base bullet and changed the rear sight leaf the performance would be adequate. It is why flat based .30-06 outperformed the heavy boat tail bullets for wounding. The boat tail worked better for long range.

          • jcitizen

            All that sounds very familiar to me – I guess I can blame “old timers” disease, because it all looks like I’ve read that before. Thanks for the refresher! I imagine the Carcano did a pretty good job killing JFK though – I hate to think about that.

          • Kivaari

            You can read an excellent report on JFK in Wound Ballistics Review 1995 V2N2. By Dr’s Lattimer, entitled Differences in the Wounding Behavior of the Two Bullets That Struck President Kennedy: an Experimental Study”. Another article in the journal is by Fackler entitled “Tests Prove that the Pristine Bullet does not Support a JFK Assassination Conspiracy”. Fackler and I did some correspondence in that era when the International Wound Ballistics Association was running full speed. You local library should be able to get you all the articles and all the articles and studies referenced in the footnotes. I received pounds of material from the US Army, Sweden, Yugoslavia and China. All had worthy material. The Swedish material was distorted in an attempt to discredit the US Army using the M193. It is much more effective than the barracks room talks.

          • jcitizen

            Actually I’ve been readking LIFE magazine – watching TV specials, Scientific American, and gun magazine articles about it for years, even before the internet came out. I don’t know if it was Fackler, but the studies were very interesting, especially in how one of the bullets that went though his neck took a tortuous journey through Governor Connally’s body. It is all very morbid, and I got such a fill of it when I was young that it just makes me sick to my stomach – I don’t believe any of the second shooter conspiracy theories any more – even if there is room for other bad tidings, I just blame the Secret Service for not doing their job, and I will look at that very closely if it happens again. God help us!

          • Kivaari

            There was NO MAGIC BULLET. There was no “tortuous journey” involving the bullet through Kennedy’s back. That is why all the popular press garbage is wrong. It is why using the actual evidence and not some made for TV or Life magazine article is worth reading. The bullet that hit both Kennedy and Connally traveled in a pretty much straight line. The two men were not sitting on the same level plain. Connally and his wife were seated on “jump seats” that placed them lower than the Kennedys. If you want the real data, read the WBJ and the Warren Report. I’ve seen pretty much all the popular media and have seen two pretty good videos that actually address the facts. If you want to see the real images, read the referenced material.

          • jcitizen

            Sorry if I implied that – the study that I believed did in fact prove it was in a straight line – but the angled path was popular early in the misunderstanding of the incident. My uncle once shot a rhino with a 7 mm Mauser with the then new long Spitzer boat tail bullet, in the 1920s, and he could not believe the path the bullet took, but that was a special case, where the bullet was bent on impacting the bone and armor of the huge animal and changed course in its journey. He checked it out when he butchered the animal. I still have the bent bullet from that African hunt. I think this is where the legends come from, but the physics don’t actually stack up in the same way for JFK assassination.

          • Kivaari

            A disadvantage of the 6-7mm heavier bullets is it takes more powder and thus case size and recoil to match the trajectory of the smaller bullet. A little bump up in caliber, while retaining the ballistics means everything grows. Or like the 6.8mm the performance drops as well as magazine capacity. The best thing to make a 5.56mm a better performer is to install great glass, triggers and training. Any hole in a person makes them sick or at least hurting. They all diminish the functioning of the target.

          • jcitizen

            If there is a problem with some of the modern 6.8 or other cartridges, it is that they insist on making it fit the AR16 system instead of a down size on a 7.62x51mm. I’m getting tired of the whole thing though; and am beginning to feel that development is stuck much like it was in the early 1800s when muskets didn’t change much for over 60 years.

      • Of course, the fact that the M16 was already inflicting more effective wounds the whole time (right up until we started using M855 out of carbines, often at ranges well beyond those that have dominated typical infantry combat since the end of the Boer War) is disregarded, so I expect the Big Bore fanatics to disregard this development… at least until it is fielded and available in 7.62x51mm…

        The 7.62x51mm and similar *does* inflict more serious wounds… at 1000 yards, or against horses. Which isn’t surprising, because all of those cartridges were basically designed to disable or kill a horse at 1000 yards or so, so they could keep direct fire artillery off infantry, especially within the effective range of late Nineteenth Century cannister.

        But humans are simply too insubstantial a target at typical infantry ranges for the additional power of the “full bore” cartridges to really shine on, because they generally are *exiting* the body about the time they are significantly yawing… The destruction you do the landscape *behind* your target is irrelevant – only the destruction you do *to* your target matters.

        • RegT

          “because they generally are *exiting* the body about the time they are significantly yawing.”

          Not according to Dr. Fackler.

          • Go back and reevaluate his work, keeping in mind how thick the typical soldier’s torso is (not an obese gamer), and throw in a correction factor to account for the effective voids in the human body (as opposed to the homogenous muscle tissue that ballistic gelatine simulates).

            Rounds showing significant yawing at 20cm would be *exiting* the human body at that point. Where does M80 ball show significant yawing? Beginning about 20cm…

    • iksnilol

      Just imagine what a bullet like this could do in for instance .308 (with a “light” 100 or 124 grain bullet)?

      • The Wound Channel

        That bullet is in development and will be in use soon. That is a terrifying concept lol. It will be called M80A1

        • iksnilol

          I can’t wait.

          I wonder how the effect is after penetrating a barrier? Like shooting through a concrete or cinder block wall with this and into tissue.

          • ostiariusalpha

            The M855A1/M80A1 bullet uses the copper jacket to create an expanded wound channel on unprotected targets. The jacket tends to get ripped off when piercing thick barriers though, but the steel penetrator and copper core make it through and create two seperate wound channels that are pretty effective even with the loss of the jacket.

          • jcitizen

            I’ve found the whole video thing about the M855A1 on video to be very fascinating here on TFB; or at least I’m pretty sure it was here that I saw that article. A test of the new NATO round would be just as fascinating to me! I hope either one becomes available out of Lake City or some where before long. Several types that are just as good as the M855A1 are available in civilian ammo, with similar military designations, but I don’t have a barrel with the right twist yet – so it will be a while before I get a good upper that can use it.

        • jcitizen

          No one is admitting now days in something that came out not long ago in two part powder that turns your rifle into a veritable rail gun! The rockchuck hunters in Eastern Colorado were using this science to great dispatch in their favorite weapon of choice – the short barreled Thompson Center rifle – it is the only rifle I know that can get past the BATFE regulations, because that company won a Federal law suit to get it approved! They used a special intermediate cartridge with a fat base and a sharp shoulder medium length round that could get a full high velocity result out of a 10″ barrel. I have not heard of it since, as if it became a national secret or something. I know for a FACT that it was successful because I live in the desert southwest, and know a lot of varmint hunters from that entire area. I don’t remember the bullet diameter, but the case may have been at least like a cut down 22-250 case. All I know is that they were getting phenomenal velocities from their wildcat cartridges – I think the powder was from a French maker, but I’ve since forgotten many of the details. I’m pretty sure it was a smaller caliber than the M80A1, and a shorter case. I feel it was a true intermediate round design. Fat chance NATO would approve of it of course; I just had to say something to get it off my chest.

          • iksnilol

            Sounds cool.

            three base powder is even better, even faster without increased pressure.

          • jcitizen


          • iksnilol

            Seriously, google that stuff. It’s been used in cannons for many years.

          • jcitizen

            Well – I knew that the 40mm grenade did it by using a two part chamber, but that isn’t the same thing. The fast powder went into the primer chamber, and the slow powder went under the round for liftoff. Firecracker makers have been doing that for over 300 years. This powder did it just by loading it in a regular manner, and I’m pretty sure the primers were standard as well. So apparently the initial primer phase would ignite the fast powder no matter where it was in the mix, and the slow powder would play catch up as the bullet went down the bore. It would create a very flat pressure curve in the testers, and not a spike like most normal powders.

          • iksnilol

            I don’t know how it works, they just use multiple chemical bases.

            Provides more smoke though, but less muzzle flash and muzzle temperature. Also it stores better.

      • In .30, a bullet as light as 100 or 124 grains is a bit short. It will also have lousy mid to long range performance, because the sectional density is low, the drag is relatively high, etc.

        And your trajectories will change significantly, requiring the purchase of all new sights, across the board (because, AFAIK, *all* 7.62x51mm sights in US military service, aside from pure mil-dot sniper scopes, have BDCs built in, if only the range settings on the iron sights).

        No, this configuration of bullet, at about 150gr, would be awesome.

        • iksnilol

          Ah, think outside the box: Just make a hollow base or make a part of the core hollow to save weight and increase length.

          The M855A1 bullet config does get a good share of its power from velocity. Scaling it up while reducing velocity doesn’t seem like the best idea to me. It’s a decent idea but not the best. Maybe the most practical and doable though.

          • Yeah, “long and light” didn’t really payoff.for the CETME, IIRC.

    • You just wait for the .30 caliber myth to finally become a reality with M80A1

    • RegT

      Dr. Fackler wrote about the temporary wound cavity effect, and stated it is over-rated as far as significant damage to the tissues involved. This looks dramatic, but _might_ not actually be superior to the damage from a larger round like the 7.62×51 NATO.

    • buzzman1

      Only to what 60 years or so for the .5.56 round to exceed the standard 7.62 ball round which, is still needed for long range engagements.

  • Jon

    How about the amount of energy it needs to perform as we see here and the usable range with each barrell lenght?

  • Plumbiphilious

    Dear sweet heavens. I never knew you could make a bullet that makes gel fart out its own burning self. I want to know if that effect reliably seen in further gel testing?

    • JamesG3

      This round’s nickname should be Montezuma’s Revenge.

      • Uniform223

        nah… call it “The Ex-wife”

    • The Wound Channel

      Yes with a camera capable of this frame rate you can repeat that explosion.

    • Chuck Haggard

      I’ve seen a number of rifle, and some pistol testing, where the flash happens, it’s nothing special to do with this bullet, in any way, it’s due to the type of gel used.

  • marine6680

    There is actually a phenomenon that causes a flash of light due to cavitation and vacuum… it’s been documented when studying mantis shrimp.

    May be a similar thing here.

    • jtciti

      It looks like simple dieseling, which is clear from the carbonized exhaust being ejected. Sonoluminescence/cavitation effects occurs in the absence of a flammable or combustible medium (IE water) – basically the ignition of a a fuel in this case prevents the bubble from collapsing fast/far enough for that phenomenon to occur.

      • ostiariusalpha

        Right on. William mentions that he doubts the dieseling effect would occur in organic tissue, but if you got a gut hit I think you could get ignition of the flammable intestinal gasses.

        • Tassiebush

          I wonder if thick abdominal fat could diesel like that too.

          • The Wound Channel

            It’s possible human fat could burn I guess, but likely not in the same fashion as this gel.

          • Tassiebush

            Yeah i guess it wouldn’t be as thick and encompassing as a block of gel.

          • Edeco

            Yeah, pretty sure vaporized fat could go off if treated right, but I don’t think tissue would pull back together hard enough to cause it. Don’think… but then I was surprised by the gel doing it.

          • Tassiebush

            Yeah it’s hard to say. When I’m cutting up cryovac slabs into steaks I generally throw the thick fat offcuts into the fire and it burns really easily but that’s a pretty different context. I’m imagining a side on hit to an impressive beer belly πŸ˜‰

        • COL Bull-sigh

          Or how about the effect of going through the fat of a plump skirt-wearing pervert Mudslime terrorist. That ought to produce a nice little secondary.

      • marine6680

        I have been unable to view the video so far… I will have to take a look when I get the chance.

        The two effects would definitely look different.

    • Nope. Not at all the same. This is old fashioned dieseling, from flammable fumes (this gelatine is a flammable hydrocarbon) being squished.

      Sonoluminescence is orders of magnitude higher pressures.

  • uisconfruzed

    VERY impressive!
    Why did it look like two rounds at once?
    I understand it fragments, but that looks like two separate bullets exiting.

    • Joshua

      Because the steel tip breaks off onto its own path through the body when the bullet fragments and the copper slug continues forward. You essentially get 2 exit wounds from the same bullet.

      • The Wound Channel

        That is correct. Plus the steel part facilitates penetration through extremely tough barriers while still providing devastating soft tissue damage.

        • TJbrena

          Have you considered making a video of M855A1 vs AR500 plate? You did one with M193 vs M855.

          I’d like to see if the A1 penetrates any better, or if – in the case of no first-shot penetration – the A1 would penetrate in fewer shots.

          • The Wound Channel

            I have shot M855A1 into Level III, and two different kinds of Level III+. The videos are on my channel.

          • TJbrena

            I didn’t realize that. My bad, I’ll go check them out.

  • iksnilol

    Holy crap. I am so getting a 5.56 rifle if this stuff becomes widespread.

    At what distance does it have that fancy blowing stuff up effect?

    • That’s probably a side effect of the gel, and I doubt it would be likely to happen if a human target were struck. However, even without it the round’s plenty dangerous.

      • iksnilol


        5.56 finally has merit for my personal uses.

        • I think it probably did before. After all, from what I can tell M193 is the leading hog hunting round here in the US.

          • iksnilol

            I don’t hunt yet. But I think I’d take something with a bit more authority than M193 (especially considering that’d be illegal to hunt with in most European countries).

          • Then so would M855A1, I imagine.

          • iksnilol

            Basically. It’s a FMJ. Norway demandeth that SP or other “hunting” ammo is used (AKA anything not FMJ that is suitable).

            Still, the M855A1 is more impressive than the M193 to me at least. What I wonder about is brush and barriers with these lightweight rounds. A lightweight “zippy” round is more likely to be deflected of course by brush and crap in the way, right?

          • ostiariusalpha

            Basically, no bullet likes brush & crap, almost regardless of it’s weight and caliber. It’s been tested under various conditions that any obstructions that would cause excessive deflection in a 5.56 bullet will do the same to a 7.62 pill. As long as the projectile has the oomph (mass/velocity) to get proper penetration, that’s what really counts.

          • Kivaari

            50 years ago we played with the brush whacking advantages of big bullets over small bullets. What we found, when shooting through green brush, is every bullets goes to pieces and is deflected by branches of any size. Not scientifically repeatable, since we just used natural vegetation. But it showed even .30 caliber FMJ bullets disintegrated upon hitting one or two branches. Brush-bucking is a myth.

          • ostiariusalpha

            Indeed. Even the “Clobberin’-time!” punch of the .50 BMG gets deflected by a surprisingly small amount of obstruction.

          • jcitizen

            Yep! Oh how I know after about 5000 rounds fired since I was a young man, and also even more during training in the US Army!

          • jcitizen

            Back in the bad old VHS days there was a video available that actually documents just how disappointingly ineffective any round from .22 to .50 cal can be when deflected by brush, car bodies, and standard window glass pane! I was gob smacked when I saw it way back then! Don’t remember the name of the video – sorry! We had since found every thing they showed on there to be true, in the junk yard and playing with armor plate and several AP military loads.

          • iksnilol

            Bricks are scientifically repeatable brush πŸ˜›

  • Heretical Politik

    The flash is sonoluminescence… at least that’s what’s been explained to me.

    • TechnoTriticale

      re: The flash is sonoluminescence.

      Nope. SL doesn’t result in brown smoke.

      DOD better hope EPA doesn’t catch a whiff of this. ☺

    • Nope. Nowhere *near* the required pressures to create sonoluminescence. This is old fashioned “hydrocarbon fumes detonating in a Diesel fashion”, because the gel is a petrochemical, not an organic gelatine.

  • nova3930

    Yah, that’ll do. Wish I could get my hands on some….

  • The Wound Channel


  • @nathaniel_f:disqus
    With this type of bullet construction, would a 5.56 FABRL in an aluminum case be a possible 5.56 NATO replacement in the future?

    • Impossible for me to know. According to an inside source of mine, M80A1 required a great deal of additional development despite being basically the same concept. Apparently very close attention must be paid to the bullet’s exact configuration, weight distribution, etc. to maximize performance.

      • The velocity difference probably gave them major headaches, too.

  • Kyle

    Neat! I want some!

  • HenryV

    I wonder how fast a bullet would have to go to burst the block? Or should that be how much energy would it need to dump?

  • Sandydog

    That there bit of nastiness surely looks like a fuel-air explosion! Given that the human body is just a mess of gases, jellies and meaty schmoo that will burn or even explode if you vaporize it and expose it to intense heat, just like any other carbon-based material, this round just might step on a few toes at the Geneva Convention. I don’t think that we’re allowed to blow up a guy from the inside out–we’re limited to just poking holes in him, aren’t we?

    • Chuck Haggard

      It’s nothing to do with this bullet, it’s an artifact of the type of gel used, this happens with lots of bullets shot into this type of gel.

      • Sandydog

        Good to know–of course, try explaining that fact to Nancy Pelosi.

    • CommonSense23

      Look someone who has no knowledge of what they are talking about and spreading bad info.

      • Sandydog

        Oh, look, somebody taking themselves ‘way too seriously!

    • *IF* it actually did that in tissue, yes, it would violate the rules against explosive projos below a certain weight.

      But it is due to the chemistry of the gelatine here – this stuff (unlike the old style organic gel) is petrochemically based.

      • iksnilol

        Not really, since it doesn’t have an explosive or incendiary component.

  • knighthawk12

    The down side is I can see some antigun libtard calling that an exploding bullet and demanding its immediate banishment. Just from seeing the reaction and having no knowledge of the cause and fact that a body would never support that reaction.

    • Orion Quach

      Pretty sure we plebains can’t even get our hands on it to begin with because it’s actually armor piercing.

      • Currently, it is treated exactly the same as M855.

    • Michael Valera

      Keeping it no politics… mmmmm no.

    • They’ve been saying that about the 5.56x45mm since Vietnam. You bought tonread some of the DTIC papers on the efforts of the Red Cross trying to declare effective ammunition to be “dum dums” and trying to use tht misclassification to invoke the moribund Hague Conventuons where the Conventions do not apply.

    • jcitizen

      They’ve been saying that about the 5.7mm developed by FN too. You just can’t fix stupid with them!

  • coyote-hunter

    That’ll ruin your day!

  • Thomas

    I use a .308 for deer hunting . I doubt this would outperform a hornady light mag , 165 gr at 2880 fps, or another deer load , 150 gr at 3000 fps, using an expanding bullet.

    They just drop and go nowhere .

    • It might not create as large a temporary or permanent cavity, but I bet it performs more consistently, and I know it penetrates more, while weighing half as much.

      Again, this is a military bullet designed for military needs. I doubt when out in the deer blind you care how much a round of ammo weighs, but the military sure does.

      • jcitizen

        Our state finally legalized the 5.56mm for deer hunting, much because of the continued effectiveness or the round, and also the huge popularity of it.

  • Chuck Haggard

    Actually, this rounds gives average performance in gelatin compared to other 5.56 rounds currently available. There is nothing at all special about it, especially considering that other bullets as good as or better were available with the military having to spend millions and millions is “research” just so they could steal the design from a small company and end up getting sued over it.
    It’s also over loaded, to near proof load pressures, and it causing premature wear and tear on carbines and SAWs.


      M855A1 isn’t the only fleet yaw independent round out there, but it’s one of the few. A lot of research went in to making it perform that way. Also, keep in mind that it has good penetration characteristics, unlike most of the civilian rounds on the market.

      The idea that the Army stole LA’s idea is not compelling to me; I’ve seen no evidence that LA has done the sort of research that went into producing the M855A1 round, while I have seen their patent portfolio, suggesting they were taking shots in the dark patenting a lot of different bullet configurations.

      I can’t say for sure that LA was patent trolling, but I can say that the ARL’s research which led to M855A1 is real, not fabricated.

      • jcitizen

        Seems like using the right twist rate would result in standard wear and tear – maybe not. Chamber throat erosion was always a problem for the 5.56mm anyway, because of the high velocity. Since the bore is still touching only the jacket the wear should be similar, in my best guess. In fact maybe less, because I think the velocity is still less than the SS109 but higher than the M855.

        • Kivaari

          The 5.56mm doesn’t really have all that much velocity. It has been mentioned for 55 years as being this dastardly high velocity load that it has seeped into the common knowledge. Compare it to other military rifles, throwing 150 gr. bullets at 2800 2950 FPS. A couple hundred more FPS for the 55 gr. bullet doesn’t really make it HV. Then add a 62 or 77 grain bullet and all of a sudden it is just another bullet flying at speeds under 2900 FPS. Throw a shorter barrel into the mix and the 5.56 is simply “normal velocity”. If these flew at 3900 FPS, then I would accept that definition as being higher velocity than those rounds currently in issue. There is no magic going on.

          • jcitizen

            I know a LOT of Remington 788 .223 cal varmint rifles shot out by 40 grain reloads that reached the same velocities. 2900 fps is still pretty good velocity by any measurement I’ve ever read or been told by experts. Besides my NCOIC at MATES explained that was the reason he measured for this on the inventory we had, and 10% of our weapons had the barrels changed out for that primary reason. This would cycle out every three years on average, when not deployed. Some of them were trashed for bore problems but the chamber throat erosion was the more common cause.

            Although it is true that this speed is a common velocity for military rifles now, that doesn’t mean it isn’t in the same category as before. I would also contend that an M4 has the same chamber forces on it as the longer barreled rifle even if the resulting muzzle velocity drops with shorter barrels. In fact the figures I see show the M855A1 cartridge increasing chamber pressure from the old 55.000 psi to over 62,000 psi – so this could aggravate the problem even more.

          • Kivaari

            MY point is, at 2900-3000 FPS it isn’t a high velocity cartridge. Heat and the abrasive powder going across the throat wears out barrels. That is why so much research has gone into making barrels tougher, using powders with less abrasiveness. It is why hammer forged barrels outlast conventionally cut barrels. The M788 was a cheaply made rifle. Dropping to a 40 gr. bullet at higher velocity increases the wear. Like a S&W .357 revolver. Using the 125 gr. loads so popular 40 years ago, caused excessive wear. Going to 140-160 grain bullets, still at high speeds caused less wear on the throat. The barrels used then were conventionally cut. Today S&W is using button rifling on many of the new revolvers. That in itself, increases the ability to resist those forces. It is why I am willing to pay more for an AR15-type rifle to get a hammer forged barrel. When buying the excellent BCM uppers that extra $100 is worth it to me. Even knowing I will never fire enough rounds to wear out a cheaply made barrel. I like forged uppers and lowers, and distrust billet parts. I have no basis in whether or not billet parts are less sturdy. I just like forgings. It comes from a misspent youth watching my dad at the foundry.

          • jcitizen

            I still consider anything approaching 3000 fps as high velocity – I know there are specialty rounds and SLAP that approach 4000, but they are not generally considered practical for most purposes in small arms the military. SLAP has its uses, but I read that they are not accurate enough to be really useful yet. I agree with everything else you are saying. Of course if you look at experimental rail guns, then yes – anything below 6 miles per second is very slow by comparison.

    • Fegelein

      Hush, you’ll make Nat cranky and he’ll have to say why he’s right and you’re wrong, and it’ll be because he says so.

  • The G&A article is the source of a great deal of misinformation about the M855A1. Let’s take their alarmism about the round’s high maximum average pressure (MAP). M855A1 has a MAP of 63,000 PSI, compared to M855’s 55,000 PSI (that bit is true), but why? Back in 2006, NSWC Crane engineer Charles Marsh and his team discovered that the propellant being used in M855 and Mk. 262 up to that point, which was WC 844, suffered from extreme pressure excursions at temperatures above the 165 degree standard NATO testing threshold. These temperatures, such as might be found in the hot chamber of a gun fired on fully automatic for extended periods caused M855 to reach pressures of up to 90,000 PSI.

    A new thermally-stable propellant was developed for Mk. 262 to fix this problem, and later a derivative SMP-842, was used in M855A1.

    M855A1 can get away with a 63,000 PSI chamber pressure because it doesn’t suffer from those pressure excursions (as much) with temperature. Therefore, the MAP can be raised. Conceivably, yes, firing slowly M855A1 could wear out a firearm’s barrel more quickly than M855, but that is not what the military is worried about. They are worried about firefights like Wanat where weapons reach temperatures of 300 degrees or more. In those situations, M855A1 is actually safer.

    In fact, Spiral 2 M855A1 uses a reduced MAP of 59,000 PSI, to help alleviate concerns from the USMC about the round’s higher pressure, with the aim of standardizing the rounds between the two services.

    The Guns & Ammo article is a poor source for any information regarding M855A1. I would recommend these instead:

    • jcitizen

      Makes me want it even more – I’ve known for quite a while you got to choose your barrel carefully if you plan to use military grade ammo in it. I learned that at a very young age – unfortunately.

  • Yes, and if you read it, it mentions US Patent 7748325, the patent that Marx is claiming the Army is infringing upon. Note that besides having three-piece construction, it doesn’t really have anything to do with M855A1:

  • David Ruff

    but an explosive round WOULD be nice

  • Kivaari

    Nathaniel, This is just a little puffery. TFB and your references has really done a great deal to improve the gun knowledge of the general population. We can give credit to the Internet generally, but TFB has really given access to information much easier than when I was actively involved in doing some research. Good job all around.

  • Miguel Raton

    Think you’re gonna need ballistic soap to get an accurate representation of the wound ballistics on this one; that dieseling after f/x from the gel is hilarious to watch in slo-mo, but completely destroys any validity of the results. “Hey Bubba, watch me make this block of gel fart!” πŸ˜€

    • Or, the old style organic gelatin. The new clear gel stuff is great for a lot of reasons, but, yeah, I’d like to remove the “dieseling” variable and verify that that secondary detonation doesn’t significantly affect the permanent wound channel.

  • Emilio Zapata

    thats a Geneva convention violation

    • How? The Geneva Conventions do not even address small arms ammunition…

      • jcitizen

        Let alone gel blocks! HA!

  • talon55101

    Looks like a FAILURE to me. There is a piece of the bullet (base) near the entrance (fragmentation) and there were two projectiles exiting (jacket and core), complete seperation. Good temporary stretch cavity but, FAIL.

    • iksnilol

      That fragmentation is good against unarmored stuff, that stuff penetrating and separating is good against harder stuff, + two wound channels are better than one.

      • talon55101

        Let me rephrase. It violates the Geneva and Hague Conventions. Meaning ILLEGAL, Meaning FAILURE.

        • iksnilol

          How does it violate the Hague and Geneva conventions?

          It doesn’t expand, flatten easily or easily change its form in the human body. It doesn’t have an explosive component, it isn’t incendiary and it isn’t poisonous.

          It isn’t a failure. Falling apart isn’t really changing its form.

          • talon55101

            It doesn’t change it’s form??? Look again. You forgot fragmenting which it CLEARLY does by DESIGN.

          • iksnilol

            It just goes into pieces. Shoddy Western quality.

            Nothing to see here, comrade.

            In all seriousness, fragmenting is alright since it minimizes collateral.

  • Guido FL

    Time to use some nonflammable gel and do a retest ?

  • COL Bull-sigh

    Thank God the US did not sign the Small Arms Agreement at the Geneva Convention, which mandated FMJ rounds only. Maybe this will equalize us with the improvised “X-heads” carved in the tips of the AK ammo fired at us by the Mudslime extremists.

    • jcitizen

      They should go back to square bullets like they used in the Puckle guns shooting up the infidels centuries ago.

    • iksnilol

      Eh, the M885A1 is a FMJ.

  • Scot168

    Watching the slow motion footage over and over several times, I started to feel sorry for the gelatin.

  • They’ve been saying that since about 1967, so…

  • maodeedee

    “That phenomena would not happen in tissue, I don’t think.”

    That’s probably true of a lot of what you see in Jello testing. Ballistic gel is not 100 per cent analogous to flesh and bone. The human body is not homogeneous as a block of Jello is, and is made up of elements of different densities, muscle, fat, cartilage, and bone.

    In Jello, projectiles always travel in a straight line. In mammals, projectile paths are often diverted partly because the mammal is often times in motion and not sitting inert on top of a table.

    When celebrated sixties pop artist Andy Warhol was shot at close range with a 32 auto, the bullet traveled almost in a zig-zag pattern and did damage to several organs and he flatlined on the operating table and they had to cut open his chest and massage his heart to bring him back to life. –all from a puny little 32 auto that would hardly do anything in ballistic jel !

    Then there was the 6.5 Carcano 162 grain bullet that shot Kennedy and wounded Texas governor John Connelly. If they had ballistic Jello testing back then they would have concluded that there HAD to be a second gunman because in ballistic jel a bullet’s path is never diverted. My point is that a whole generation has come of age believing that jel testing is absolute when it’s really just an approximation and then from that point, the imagination, along with no small amount of speculation, takes over from there.

  • Brad Ferguson

    Don’t let Diane Feinstein see this vid……….She’ll have banned as a internal exploding round. lol….

  • jcitizen

    Too bad this round can’t light up prairie dogs like that get! Good thing it doesn’t on deer meat though! HA!

  • BigFED

    OMG, bullet farts!!!

  • tenmillimeter

    I would like to have seen back to back with other standard rounds for a direct visual comparison. Scary stuff!

  • iksnilol

    “This just in! Gun people are all going “AW F*** YEAASSSSSS!””

  • buzzman1

    That phenomena would not happen in tissue, I don’t think. –
    Lots of bad guys in the world to try it out on.
    BTW what barrel length was the round fired from? Is a 20″ barrel still optimal?

    • 16″ barrel, The M855A1 was designed as a short barrel rd, so for the M4. Its powder is optimized for 14.5″
      You could go up to 20 inches, but gain almost nothing.

      • buzzman1

        Thanks John. As you probably already know the 5.56 (including 855) was designed for a 20 ” barrel and its lack of effectiveness from a 14.5 was evident.

        • It gets 2,900-3,000 fps in a 14.5″ so its quite exceptional.

  • talon55101

    John: Fragmenting rounds ARE in violation of the Hague treaties. There are gray areas i.e. The 5.56x45mm M-193s propensity of snapping at the cannelure into two pieces when tumbling and the Russian 5,45x39mms ENCLOSED but hollow tip that aids in bullet upset, speeding up the tumbling process increasing it’s lethality. Whether the M-855a1 was designed to fragment or not doesn’t matter. That fact remains IT DOES. Hence ILLEGAL for use in warfare.