Poison Pill Indeed – 7N6 Out of a Krinkov

Capture

I, for one, am glad we have never had a real all-out shooting war against the Russians. Their 7N6 is a nasty little ball round, designed from inception to tumble. To see just how much trouble the 5.45 round is, MrGunsNGear did a quick gel-block test using a Krinkov.

I can see why they were called poison bullets. Nasty little things tumble well within 12″ of a gel block!

 



Nathan S.

One of TFB’s resident Jarheads, Nathan now works within the firearms industry. A consecutive Marine rifle and pistol expert, he enjoys local 3-gun, NFA, gunsmithing, MSR’s, & high-speed gear. Nathan has traveled to over 30 countries working with US DoD & foreign MoDs.

Nathan can be reached at Nathan.S@TheFirearmBlog.com

The above post is my opinion and does not reflect the views of any company or organization.


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  • Zebra Dun

    Any Shots done through a denim covered block?

    • iksnilol

      I doubt denim would do much to stop it.

    • Giolli Joker

      Although more testing is surely interesting, I can hardly think of denim having any effect. It is an important test for pistol hp bullets as it tends to clog the cavity affecting expansion… on a pointy rifle bullet it will probably be totally ineffective.

      Short barrel, short range, I’m pretty sure the tumbling has a lot to do with the fleet yaw we saw in the recent Vickers’ video posted by Nathaniel.

      Sexy SBR, btw.

      • Zebra Dun

        Just for the sake of another test wouldn’t you like to see it again in Denim?

    • BryanS

      Why? Should Jay Leno be worried?

  • Tyler McCommon

    Well too bad 7N6 is all but gone.

  • Will

    I’m impressed with the rounds performance.
    NOT impressed with this clowns muzzle awareness. How many times does he have to change position of the muzzle of a loaded rifle????
    And pointing it at the camera was just asinine!!!!!
    SAFETY, SAFETY, SAFETY!!!!!

    • Marc

      The camera is on a tripod. Nobody was at risk.

      • Anton Gray Basson

        Doesn’t excuse it. Teach by example.

        • iksnilol

          Oh noes, he pointed the rifle at the camera (an inanimate object).

          THE HUMANITY! OH THE HUMANITY!

          • Anton Gray Basson

            Ok fine he pointed it a camera. Whats behind the camera? Is it a suitable backstop or sufficient distance occupied by nothing to ensure that nothing is stuck by the bullet? Maybe its a home, car, road ect? This is my biggest gripe with shooting videos from the states is that they seem to be extremely unsafe venues.

          • Marc

            What’s behind the camera is of his concern.

          • -V-

            Oh Noes, he didn’t include a survey report and a topo map to demonstrate that indeed what was behind the camera was a suitable backstop!! Oh Noes!

            Chill dude, its a gel block test video. Enjoy it for what it is instead of trying to find every little thing to nit-pick about.

    • Some Dude

      If you can do better then start your own YouTube channel. If not then STFU and get back to playing Call of Duty where you belong.

      • Wolfenstein

        @some dude You can’t be serious…

        • Some Dude

          I am serious. Mr. Gunsngear has addressed this issue before. I for one am tired of YouTubers doing worthless press checks and racking slides repeatedly in order to appease the safety patrol. Normally when a YouTuber does one of these actions they will verbally say something to the effect that the weapon is clear for all of you who are concerned. I can imagine that they do so because they are tired of getting comments and emails about safety.

          • Dracon1201

            Agreed. Mr.gunsngear does not compromise safety. If you Safety Nazis want him to be truly safe, you should demand that no YouTuber should ever shoot on anything but a square range. That wouldn’t be very fun to watch though, would it?

      • James

        One of the best things about the shooting community is that people are always and everywhere safety conscious. You cannot tell someone to go piss up a rope because they’re trying to keep others safe.

        • mosinman

          there’s a difference between being safety conscious and going over the top.

    • AJ187

      Yes, his constant fidgeting made me crazy. I don’t even care if it was loaded, it was just distracting and annoying.

  • iksnilol

    I never understand why they never do gel tests at longer distances. I would be interested in how it performs at ie. 400 meters.

    • WojtekimbieR

      It would be hard to hit the center of the block at that distance. Gelatin blocks are expensive and problematic to use, and you only have one chance to get a good shot.

      • Zebra Dun

        A rifle with a low minute of angel and an expert rifle man cannot hit a gelatin block at 400 meters?

        • R H

          Even if you were shooting a 1 MOA rifle @ 400 meters (Assuming your aim was dead on) you could be 4.5 inches off center. The cross section of this target is 6 inches x 6 inches. On a service rifle the results would be even worse. Assuming 3 MOA you might not even hit the target at that distance. Like WR said above you, these blocks aren’t cheap and you have to keep them at a certain temp for the test to be valid.

          • Kivaari

            30 years ago I looked into buying a 100 liter drum. It is very expensive.

      • iksnilol

        Regarding the precision, why not build a bolt action in the caliber (first justification for a 5.45 bolt rifle with a short barrel?)? To ensure as perfect accuracy as possible.

    • Zebra Dun

      I agree at least go out to 100 yards as this is the optimum range for it.

    • Vitsaus

      I think 100-300 meter tests are more reasonable for these micro caliber rounds, as well as practical combat distances. At least in the case of this video the short barrel sort of limits the range that one can adequately test the cartridge anyway. From what I’ve read about the 74 short barrel variants, it was never designed for much farther out than 200 meters, especially since originally it was meant for vehicle borne troops.

      • Kivaari

        A friend with an SOT has a machinegun variant. He says it is hard to hit even at 100 yds. It’s a real beauty.

    • Gel tests are very difficult to do at those ranges, and “simulated” long range tests (by downloading the propellant) are invalid due to the fleet yaw effect, among other things.

  • MPWS

    You saw them and used them – in hands of proxies in Ukraine. There is plenty of video on subject. Yes, nasty as war can be.

  • From what I’ve read, the one advantage of 5.45 over 5.56 is that it reliably tumbles upon impact out of shorter barrels.

    • 5.45 does tumble readily, but it still suffers from fleet yaw – the same problem that plagues M855.

      • CommonSense23

        Its honestly a lot more than fleet yaw that plagues the M855.

        • It’s not the only thing wrong with it, no. The designers of the SS109 made a few assumptions that didn’t prove to be true, and the round has proven to be problematic to make consistently, and erratic in effectiveness. It also has a longer neck during yaw in tissue more often than its design suggests it should, which could be caused by a number of factors.

          • Joshua

            SS109 was designed to penetrate soviet steel helmets at 600M from the M249.

            fragmentation was not the main design goal of it.

          • They did want to retain the best characteristics of M193, but it seems they didn’t fully understand the problem.

  • MountainKelly

    Wish 7n6 was still dirt cheap. AP my ass. Oh well

  • DIR911911 .

    so basically you could get shot in the shoulder and have it exit your bellybutton , got it.

    • Kivaari

      The 5.45mm does usually make a bi-lobed tumble, coming to rest base forward. Because it is so tough, and doesn’t break apart, the wound is shaped like the bullet, however it is oriented as it passes through “medium denser than air” (tissue).
      Like most rifle bullets at reasonable ranges if it hits fluid filled tissues the organ can stretch beyond a temporary range and fracture. A full stomach will often fracture. Empty intestines are quite resilient, and can be surgically repaired with normal sutures.
      The early reports out of Afghanistan ’79-’89 about the overly destructive wounding ability of the 5.45mm were not compared to wounds caused by other common combat rifles. A hit to the upper arm can amputate it, but so could a hit with a 6.5mm Carcano bullet 100 years ago.
      5.54mm bullets recovered from gel and tissue are normally very intact. The steel and lead core shifts forward into that airspace. A more effective version would have put an aluminum or tough fiber plug in the nose. That would keep the center of gravity rearward and enhancing the tumbling effect. It is the technique used in the .303 MkVII and Italian 7.35mm.
      Any bullet passing through vital tissue will make that soldier very sick.
      The 7.62x39mm Soviet PS (M43) is exceptionally stable, and often creates a minor wound if tissue like muscle is hit.
      The use of steel cores was a way to increase the shape of the bullet without adding greater weight. It is why the AK PS 122 grain bullet has the same profile as the 7.62mm NATO 147 grain bullet. It flies flatter because of shape and keeping the velocity up. Without increasing recoil. Putting that PS bullet in a 7.62x51mm would create a flatter shooting round, but at the cost of more recoil, a larger rifle, thus sacrificing the advantages of the battle carbine.
      Finding the happy combination has gone on for quite awhile. The AK74 improved the soldiers ability to hit at greater ranges and still deliver a disabling wound.
      Our 5,56mm does its job pretty well. That is why it has not been replaced by another cartridge in the last 50 years.

  • Wolfgar

    Vindicated. I stated before, we have spent a fortune trying to achieve what the Russians have been able to achieve with out bankrupting their nation. Our new rounds ruin the upper receivers, need replacement mags or followers, and decrease the barrel life by half. INSANE! Like I have stated before, “why can’t we do this”?

    • 7N6 suffers from fleet yaw just like M855 or M193. M855A1 and Mk. 318 solve this. A tremendous amount of research and development went into both projectiles, which is why development costs were high.

      Upper receivers will eventually wear out anyway, though M855A1 does shorten the time schedule for this with existing magazines. M855A1 works just fine with existing followers and magazines, the new magazine design presents the round at a more favorable angle, reducing malfunctions with all rounds (M855A1, M855, and anything else) to a third, and eliminate the upper receiver wear issue that M855A1 presents.

      So we can do this, we’ve done it, and we did it better than the Russians did it.

      • Wolfgar

        The pressure of the new M855A1 round is very high to maintain velocity which would have detrimental effects on the M-16 platform. Yes a lot of testing at great cost has occurred with the 5.56 round. I would love to see a real world test comparison of the 5.49X39 and the latest 5.56 round. I may be way off on my suspicions but I suspect the real world difference would be slight if any. If you have any information of such test’s I would be most eager to read it. You may have better access to information than me and it would be most appreciated. Thank’s.

        • M855A1 uses propellant with higher peak pressure, but that is more temperature stable, called SMP-842. M855 and other older rounds use propellant that can produce pressure excursions in the range of 90,000 PSI or more when the barrel heats up during automatic fire. SMP-842 is much more stable, and as a result the weapons should experience less wear during extreme firing schedules, not to mention the likelihood of bolt breakages being dramatically reduced.

          The difference between M855A1 and 7N6 in practical effect would be that M855A1 is much, much more consistent, since it is designed with the fleet yaw problem in mind. 7N6 was tested during the design process for M855A1, and was found to exhibit fleet yaw characteristics similar to existing ammunition.

          http://www.thefirearmblog.com/blog/2014/08/21/weekly-dtic-m855a1-story/

          http://www.thefirearmblog.com/blog/2014/07/28/weekly-dtic-fleet-yaw-problem-improving-rifle-effectiveness/

          • Wolfgar

            Thank’s for the information. Great blog!

          • How often did the 7N6 fail to tumble due to the fleet yaw effect? I would think it would be much less susceptible due to the inherently tumble prone, weight in the rear/ airpocket design. Anecdotally, I’ve yet to see a gel test of either the 7N6, or the 60gr lead core plinking round, that didn’t tumble.

            While I read the M855A1 testing, and they said that fleet yaw was an issue with all calibers, I didn’t see any mention of to what percentage of shots with 7N6 that was an issue.

            I’m very curious to see how the new M855A1 and 7N6 perform head to head at 200-300 yards, especially out of shorter barrels.

          • Bullets will not stay stable once they hid dense media. The length of the nose is what varies.

            The report indicates that 7N6 was more or less just as susceptible to fleet yaw as M855 and other rounds. This makes sense, as the fleet yaw effect overwhelms the stability of the projectile.

          • I’m sorry, so are you saying that they failed to tumble in testing?

          • I am saying that sometimes they yaw earlier and sometimes they yaw later. Given a long enough body of dense media, all spin-stabilized projectiles will yaw.

          • Yes, but some are certainly more prone to tumbling then others, and are better at it due to their length. The 7N6 is especially interesting due to it’s rapid, double tumble profile.

            I’m very curious to see how the M855A1 compares to the 7N6 both at close (7 yards) and long range (300+.)

          • “Double tumble”? If a projectile is tumbling, it will tumble more than once. It is unstable.

            7N6 was tested in the design process for M855A1. I don’t know why it’s commonly believed that round has been ignored by Western ammunition designers; it’s been closely studied.

          • Kivaari

            The “wound profiles” as published by the US Army are an “average” and most likely to happen image. The 5.45mm usually makes a “bi-lobed” track, ending up base forward. Very similar to other tough military bullets that don’t fragment. The 5.45mm would be more destructive if it were made with a thin steel or copper jacket.

          • Right, wound profiles aren’t an “always” thing. Shotlines tend to be pretty random.

          • Kivaari

            Most FMJs end up with the base forward. The M193 gets it results thanks to that tumble and a thin jacket.

          • Kivaari

            Look at Ezell’s The AK47 story. The 5.45 is discussed.

        • Joshua

          It actually has very little detrimental effects to the M4A1, and with the most recent produced M855A1’s having slightly lower pressures of 59,000PSI and muzzle velocities of 3050FPS it alleviated any small issue that was present.

      • BrandonAKsALot

        I wouldn’t say we did it better and I wouldn’t say they did either. Both countries have different approaches and both are plagued by different issues when developing new military technology. We are tied down by red tape, regulations, and bureaucracy while Russian will generally only go for something from a state owned company/factory.

        I think the comparison above is not really fair in the fact that our small arms design does not exactly mirror the design of Russia. They have had more time in the intermediate caliber race than we have and have had a lot more time to iron out kinks. Plus, Russia just has ridiculously exhaustive testing on everything. AK’s were a lot more similar as far as construction material/method to previous weapons than the AR was for us. It’s just two very different scenarios. Look at taking up for AR’s. What has become of my life?

        As for wear and tear, 5.45 wears more quickly on a barrel than 7.62×39 does as well. It’s the nature of high pressure, high velocity cartridges. 5.45 and 5.56 both have strong and weak points. I prefer 5.45, but I like 5.56 as well. 5.45 uses a more ballistically sound projectile and the case taper makes feeding and extraction a lot easier when compared to 5.56. It also uses a lighter projectile and isn’t as high velocity which is a detractor for some. They both have barrel lengths were they perform slightly better, but it’s not that significant for the most part. 5.45 reliably tumbles, but 5.56 can fragment. I don’t personally take terminal ballistics into account too much, but that’s me.

        • In the United States, we have two or more radiograph ranges that we have used for studying small arms projectiles. I am not discounting the possibility of Russia having similar facilities applied to small arms study, however I do not think it is likely that sort of technology would be used in the 1970s to design 7N6. Fundamentally, 7N6 is of the same generation as M855, and while I believe it is a better design than M855/SS109, it does not compare well to M855A1, which is a separate and wholly more modern projectile.

          • BrandonAKsALot

            Well, when I was mentioning exhaustive testing, I didn’t necessarily mean that it was as advanced as the way the US tests. Again, different methods and perspectives on how both countries do things. They likely didn’t have the technological advantages we do here, but they have a habit of massive scale tests on equipment. Almost every Russian adoption of anything has gone through several very different prototypes and then through multiple evolutions before it’s really fielded. It’s probably far less scientific, or used to be, but it has merits in it’s own way.

            7n6 also isn’t really a “fair” comparison for m855a1 like you said. There have been several new iterations that would be better to compare like 7n10, 7n22, 7n24. They all feature more modern and complex projectiles.

          • 7N10, 7N22, and 7N24 (tungsten-cored) are all optimized for penetration, so they really aren’t comparable to M855A1, either.

          • BrandonAKsALot

            7n10 is a hardened steel core, but is the general issue cartridge and 7n22 is the improved version of that. You are correct that 7n24 is tungsten carbide. Otherwise, the others are comparible as they are updates to 7n6. Well, about as comparable as two totally different takes on high-velocity, light weight intermediate cartridges can be I suppose.

          • All are optimized for as high penetration as possible and none address fleet yaw, so they really aren’t comparable to M855A1.

          • BrandonAKsALot

            I get what you mean. The topic started with comparing m855 to 7n6 which, as you mentioned, are more similar than the current generations of projectiles that are being used/fielded, but still two separate designs for the same basic idea. It’s something you don’t notice normally (or I don’t at least), on how much the projectile development of both countries have diverged in their evolution. You’re comparing both countries 22 caliber general issue cartridges, but they both have different ideologies to their development. On that, the 7n10 and 7n22 are made to penetrate through thicker barriers and have the nose collapse and the penetrator sheer through the jacket and tumble/fragment even more so than previous generations.

          • One of the things to keep in mind, is that where terminal effect is concerned, caliber is one of the least important quantities.

            Caliber gets a lot of play because it’s important for production – you need to know the caliber, because you need to order barrels, either for testing or mass production. In terms of terminal effectiveness, though, it’s almost irrelevant most of the time (armor penetration being a significant exception).

          • Kivaari

            Caliber is important from the perspective of using less material and improving external trajectory. As you point out caliber doesn’t matter much. Getting that flatter shooting rifle by going down in bore size makes more sense than using a slower and heavier bullet that is harder to hit with. That’s what the Soviets did with the 5.45mm. It out shoots the 7.62x39mm. They also made a change to the rim thickness to stop extractors ripping through a case rim. That was smart. had they chosen a shorter bullet, they would not need that radically fast rate of twist, I suspect they could have better terminal results by going to a bullet more like the M193.

        • Kivaari

          The Soviets are not as crude and backwards as some think. They study lots of things, such as machine time, floor space, starting weight of materials and waste steel left after machining. It is why they went to guns like the PPSh in WW2. All those things were calculated.
          Going to a stick magazine a year later took that into consideration.

    • J-

      The British developed a very effective round prior to WWII that used a cellulose (wood fiber) filler in the tip of the bullet, in front of the lead core. the effect was the bullet bent into a J-shape almost instantly and did impressive damage.

      The Russians can get away with this in the 5.45×39 because the casing is short and fat, allowing for a larger powder charged with a long bullet that doesn’t eat up a lot of case volume. The bullet has to be long to have the empty space in the nose while having enough mass in the rear to maintain energy over distance, about 60 grains. This is compounded by using a steel core which is less dense than lead.

      A hollow nose FMJ, with a steel penetrator and lead core, that weighed over 60 grains would eat up a huge amount of case volume in a 5.56×45 and cause a substantial reduction in velocity.

      The limitations on the 5.56 is that the case was designed around a short, light, lead core 55 grain bullet. What you want is the 224 AR which is a 6.5 Grendel necked to .224, which is a 5.45×39 blown out to have the casing and neck taper of a 5.56. Using a 60 grain bullet, that can achieve 3,000 fps anf have enough length between the case mouth and an STANAG (M16) magazine for a long, hollow nose, lead/steel core bullet.

      If the US changes calibers, I think that should be the new standard, better than the 6.5 Grendel. The higher muzzle velocity (3,000+ fps) would give a better point blank than the 6.5. For shooters, that doesn’t seem like a big deal, but for the military, that means easier training and better hit statistics for troops who don’t have to work out bullet drop in their heads for 0-300m distances.

      • BrandonAKsALot

        7n6 is actually a 52 grain projectile and I believe the current 7n10 uses a 56gr. A lot of the commercial stuff is 60, I believe. Also, the 6.5 Grendel uses the .220 Russian as the parent case, not the 5.45×39. An improved intermediate cartridge is a difficult prospect for so many reasons. It’s all a balancing act and figuring out what’s most important, because all intermediate cartridges will have cons in some uses. You have to take into account velocity, stability, pressure, wear on the system, recoil, weight, accuracy, range, performance in xx” barrel, and probably a whole host more. All of the require give and take.

        • J-

          I didn’t know the 7n6 was lighter. The external ballistics and design limitations are still the same: long bullet, ample size void in the nose, etc.

          The 6.5 Grendel is based off the .220 Russian, which is a 7.62×39 necked down to .220 (.224 round nose bullet like the .218 bee). The 5.45×39 is the 7.62×39 necked down to 5.45, a minuscule difference in overall case dimensions, one being Finnish and the other Russian. My point was more at suggesting that to use a standard size head, we would effectively be “Americanizing” the 5.45×39 the long way around.

          Yes, there are a lot of design criteria in selecting a new cartridge. I think of anything available now, the 224 AR is the best choice. Even if it is not adopted, something new developed would be very similar to that – e.g. a 6.8 SPC shortened and necked to .224 to get the same 3,000 fps (the magic number for a 300 m point blank) with the ability to fit a long bullet in an M16 mag, just using an American case head dimension. Also,I believe no modifications to magazines would be necessary for such a round to function, which would improve logistics nicely.

          • 7N6 uses a 3.43g (52.9gr) bullet, 7N10 uses a 3.62g (55.9gr) bullet, and 7N22 uses a 3.68gr (56.8gr) bullet.

            5.45×39 is not a 7.62×39 necked down. It uses a totally different cartridge case 10mm in diameter, as opposed to 11.35mm. This is so that 7.62×39 cannot fit inside the 5.45×39 chamber and cause a kaboom, something that currently plagues 5.56 and .300 Blackout.

            300m point blank range is achievable with a variety of combinations of projectile BCs and velocities, but generally speaking you want to stay above 2,700 ft/s to achieve it. I created formulas that help approximate the BC or velocity (given the other) needed to produce a trajectory comparable to an M4 out to 500m.

          • J-

            I thought the case sizes were the same. I don’t deal with Russian stuff (almost) at all. I am surprised the Russians, who generally take a working design and run with it forever, would change case sizes.

            Your equation is interesting. I’ll have to play with it. My evaluations, were done using a military 300 meter target with a 19 inch “kill zone”, a BC of .15, and assuming a 50/200 battle zero. The idea is that a solder could aim center of mass at each target 0-300 m and place a shot in the kill zone. My required velocity to keep the drop within that range was 2,940 fps, which I rounded to 3,000.

            Historically, the Marines experienced the same thing and love the M16 with the 20 inch barrel because it achieves the 300m point blank with the 62 grain ammo.

          • I don’t see why an M4 can’t do that. With a new barrel, it runs about 2,900+ with M855.

          • J-

            I don’t know. I know that the Marines cite muzzle velocity in the selection of the M16A4 over the M4 and that the ACOG issued to the USMC has a different ballistic drop reticle to account for the 20 inch barrel.

            Still, 2,900 is in the range of my calculations since the .62 grain bullet has a higher BC (0.185 I think).

            Either way it is far better than the 2,350-2,450 fps that the 6.5 Grendel gets out of a 16 inch barrel.

          • An M16 should be getting between 3,050-3,150 ft/s with SS109/M855.

            All of this is highly dependent on things like the exact load, external conditions (temperature), barrel wear, etc. of course

          • BrandonAKsALot

            5.45 has almost the same rim size as the 5.56/.223. With minor modifications to the extractor, a 5.56 cartridge can work with a 5.45 AK bolt. I just don’t think there’s an easy do-it-all solution yet. Especially with current material limitations.

    • AJ187

      I just can’t wrap my mind around the statement that you think the Russians didn’t bankrupt their country, especially because of erroneous spending on the military. Doesn’t the fall of ’91 ring a bell? What a silly statement.

      • Wolfgar

        The Russian ruble isnt the world curency like the dollar is which enables the U.S. to create money out of thin air. The U.S. is 18 Trillion dollars in dept and growing. If the laws of economics are still in play the U.S. is the poorest nation on Earth. My comment isn’t silly which you will find out in the not so distant future. If a person has the biggest house, many expensive new cars swimming pool etc., etc it doesn’t make them rich if it was all purchased with credit. That my friend is what the U.S. is running on, credit. It will have to be payed back someday and when we fail to pay it back you will understand my comment.

        • Wolfgar

          The U.S. dept is 106% of GDP and it would take $58,437 per person to pay it off compared to Russia which has a dept of 23% of GDP and it would take $3,634 per Russian citizen to pay off their dept. Wrap your mind around those numbers. The dollar which is the world’s currency has given the U.S. a credit card to charge charge charge. We can spend money like it will last forever but if the world decides to use a different curency the charge card will be cut and the spend happy insanity will come crashing down. Other nations including Russia have to live within their budgets or they will suffer the consequences immediately, unlike this nation which keeps kicking the can down the road by increasing dept to prevent any discomfort at the presence only to make it much worse in the future. Like I stated before I havent seen any real world test comparing the two rounds, just people stating they have done the tests. I still wonder what the real world differences are and the per round cost of developing and procuring the two rounds cost each nation. The independent test I have seen favors the Russian round and if I’m wrong I would like to see the test.

          • MrEllis

            This shows an alarming lack of understanding as to how currency works, period. Tainted numbers, poor statistics and what little fact there is, so far removed from context as to be useless.

            You should consider moving to Russia if their economic outlook is so cheery.

          • Wolfgar

            Please explain how currency works rather than using insults. I do understand usury methods and scamming the public. This is not the platform to argue this subject but by all means endorse the life of credit and devaluation of peoples savings and explain how the Feds theft of peoples savings and property is a good thing, I need a good laugh. The numbers and statistics are not tainted but from Wikipedia. I never said Russia’s corrupt economy was good but I’m sure you think there is no corruption in this country that needs any oversight. The Clintons leave the whitehouse broke and are now worth 200 million dollars. Sounds A-OK to me. Yea, why would I question our impeccable leaders in government and in the Fed Reserve. Nothing to be concerned about here. Time to watch some more day time TV.

          • MrEllis

            I have yet to fling an insult your way, but you are correct about one thing, this isn’t the place. I can read talking points practically anywhere, keep this site about guns.

          • Wolfgar

            My point was the cost per value of the effectiveness our rifle cartridge. Agree or disagree is your option but if you wish to accuse me of lack of anything you will get a rebuttal. My talking point was about guns and the bang for buck we as tax payers are getting.

        • Kivaari

          It is like the world bank. While the “rich nations” have trouble getting money, the “bums” (third world) can borrow all they need. Unfortunately, we have borrowed so much that we are becoming third world, with nicer homes and cars. I know I over spent on playthings like guns and car.

    • Dan

      That’s what happens when the people developing weapons systems care more about being better than putting money in their pockets

    • Kivaari

      The Soviets had started investigating similar cartridges before WW2. During the Russian Civil War, a few thousand 6.5x50mm (Japanese) selective fire rifles were issued. They were not dumb back then. We even tried the .276 in the early ’30s. Had we done so in a more reliable rifle, we could still be using that caliber. The .280 Brit round was another attempt that was derailed by the US Army.

    • Actually this was the Soviets trying to duplicate what we had already achieved with the 5.56mm M193…

      • -V-

        Sort of. The general consensus on the 5.56 by Soviet Designers was that the wounding of the projectile was due to tumbling. So they took the M193 as a starting point and looked how they could improve its tumbling effects. The 5.45 is influenced both by the M193 and the M67 7.62×39. The M67 round was the answer to the poor terminal effects of the M43 round. The M67 introduced a large air gap in the nose. The design of the 7n6 mirrors that by having both an air gap and couples it with a long light projectile that is especially unstable in tissue and will easily tumble.

        • True, the mechanism of action they were trying to duplicate was in error. But most ordnance people at the time thought the M193’s results were due to tumbling – thus, the SS109 and the 1:7″ twist, which was as much to reduce “tumbling” (Heh.) as for any armor penetrating qualities, as the Euros were horrified by the idea of an effective rifle bullet. (Note, even the US Army thought the 1:7″ twist would “overstabilize” ammo and reduce wounding performance, when they reviewed the USMC prototype for the M16A2.)

          But, a gap or lighter core material in the nose, to induce rapid yawing (so called tumbling) in tissue due to a CG *way* to the rear if where it normally would be goes back much further than the M67. Just another example in a long line of nose light, long for caliber and weight, bullets.

  • David

    So for 5.56 lethality to be at it’s highest, it needs to penetrate the target at the highest velocity possible or at the very least above 2650 fps for the bullet to reliably and adequately tumble and fragment once it’s within the target.

    It seems the 7n6 is so rear heavy due to the hollow nose that it tumbles extremely violently even at the relatively low velocities generated by an 8.5″ barrel from a krinkov. While it may not fragment much due to the core being steel rather than lead, the vector change from tumbling seems extreme in the video.

    Nasty little round. If 7n6 weren’t so rare, I’d be really tempted to do a Krink build.

    • Bullphrog855

      There are different types of 5.56 as well. Diversity isn’t something that’s exclusive to 5.45.

      • David

        Yeah I know. We are in total agreement in that regard. I guess I was just comparing what I see as milsurp to milsurp. 7n6 to M855. I should have specified.

        Mk.262 77 grain 5.56 on the other hand is a really mean bullet.

    • Not really that rare. I just bought a case for reasonable money.

      It isn’t dirt cheap, like it was a few years ago, but it is still readily available.

  • Kivaari

    I recommend reading the US Army study on this ammo. It is the least destructive round when compared to 5.56mm and 7.62x39mm. Wounds through the guts, leaves a wound track that matches the profile of the bullet as it is oriented at the time of passage.

    • iksnilol

      Where can we find this study?

      • Kivaari

        I had a copy of the “Wound Ballistics Review”. It was a study done by Fackler’s team at the Ballistic Research Facility, Presidio, SF, Ca.
        It should be accessible through your public library. When I retired I left them behind. My efforts to recover them have failed.
        I found studies footnoted in Ezell’s “The AK47 Story”. I requested copies based on footnotes and the University of Washington provided me with 2 inches of photocopies including studies from the USA, Sweden, Yugoslavia and China. Your state library system should be able to help.
        The live animal studies showed the bullet passing through intestines or tissue without hitting bone produced modest wounds. It was just the opposite of what the media was reporting during the Soviet invasion of Afghanistan. The rifles and ammo used by the Army were brought back to the USA by Robert Brown of Soldier of Fortune magazine. He knew how to get the stuff here, and get it to the Army. The Army did the shooting. Quite a bit is found in the Ezell book. Using the footnotes opens up access to quite a few other government studies.

        • iksnilol

          Interesting stuff, will see if I can track some of it down.

          Out of curiousity: Do they mention the M67 bullet in 7.62×39?

          • Yes – the fact that it breaks apart when it yaws near 90° makes it the best military ball load tested in 7.62x39mm, AFAIK.

          • iksnilol

            Dayum, didn’t know that. I thought only it only yawed and tumbled? Didn’t know it also broke apart.

            Thanks for the info.

          • Not as violently as M193 or M855, but, yeah. And, IIRC, it has a significantly shorter wound neck than M43, so there’s that, too.

            In fact IIRC, most lead core military type ball rounds in 7.62x39mm exhibit much earlier yawing than steel cored examples, meaning more permanent tissue destruction starting sooner.

          • Kivaari

            Yes. The Yugoslavian Army study directly pointed to it. The jacket material was still tough enough to not cause nasty wounds. The M67 does tumble faster than the M43PS.

        • Um, Fackler determined that it was the Soviet M43 7.62x39mm that was such a poor performer, and that the 7n6 5.45×39 actually wasn’t too bad – superior to almost all 7.62x51mm ball loafs tested…

          • Kivaari

            Yes! Read his stuff. Read the studies done by real scientists from other nations.
            The 7.62x39mm is an under-performer. The 5.45mm is even less effective at wounding.
            In other tests, the Soviets calculated the AK74 and the 5.45mm cartridge improved the hitting ability of its soldiers to be 2.5 times better than the AKM. The combination of a very effective muzzle brake and the flat shooting 5.45mm bullet made that possible.
            Fackler was never too concerned with the bullets in flight, but what they did after hitting a person. He studied how to treat gunshot wounds. He wrote the chapter on treating vascular damage for the Army’s current text book. He and I viewed shotgun wounds and field use from different approaches. He knew that throwing a bunch of lead pellets increased the chances to wound your opponent. I viewed the risk of stray pellets as being a liability where innocent bystanders could be harmed. Not long before he and I talked about this, a nearby police agency had killed a hostage with a stray 00 buck pellet. He always seemed to view just the performance in tissue. That stray pellet performed as it should have. Police had to be concerned about both wounding and the misses. I was pushing the use of rifles, carbines and SMGs over shotguns. I was able to get our department to no longer use lead ammunition in the shotguns and switched to firing rubber baton only.
            The Yugo study addressed their cartridges compared to NATO’s.
            Fackler pointed out that the 5.45mm wasn’t much. The bullet is so heavily constructed that it does not fragment like the M193 (under 200m). It really is a tough bullet.
            The Swede’s independent study was showing how bad the M193 was, by showing how it fragmented and really made nasty wounds. They were pushing the SS109 as a means of reducing wounding ability. They wanted a kinder and gentler bullet. The faster rate of twist needed to stabilize the tracer round, 1:7 increased the RPM, which neutralized what they were after. The end result was a series of better loads that increased the ranges where they performed better than the M193. If it wasn’t for the tracer round, the twist rate could be slower.
            The Chinese studies using dogs, eventually led the PLA to adopt the current small bore rifle.
            These foreign scientists are not idiots. Moving to small bore rifles has proven to meet the needs of most armies. Our present needs are being met with the M4 and other M16 variants. The wars in Iraq and Afghanistan have given the Army quite a bit of real battlefield data. Individuals may see “massive failures”, but what is really going on? The 5.56mm is adequate for most tasks.
            Fackler’s team also pointed out how the US 7.62mm NATO often left a tissue wound that was similar to 9mm, ,45 and .38 Special ball ammo. So similar that a surgeon could not tell the difference.

          • No, 7n6 doesn’t fragment like M193 or M855, but it (in the illustrations Fackler published that I’m thinking of) showed a *very* short neck, rapid yawing, and an extreme curvature of path, causing a *lot* of tissue destruction compared to most other military rifle rounds (the long for caliber design helps a lot). Not as good as M193 or M855 (when they hit at 2700fps or faster), true – but making it superior to most other choices.

            His illustrations of what 7.62x51mm M80 and 7.62x39mm M43 do (or rather, *don’t* do) were eye-opening to me as a young soldier.

          • Kivaari

            When they shot live critters with the 5.45 the temporary cavity, which is pretty much meaningless, was large. The permanent cavity was not. The holes in bowel or muscle were just an outline of the bullet as it was oriented as it passed. The bi-lobed path is quite common in rifle bullets dating back a hundred years. The permanent cavity simply wasn’t much. Go back and look at the diagram, that “big cavity” is the temporary stretch. That’s the “dotted line” portion of the illustration.
            The 7.62 M80 is built stronger than the FN produced and leaves smaller wound tracks. As the illustration shows, it leaves a wound track pretty much the same as a 9mm or .45. That FN load goes to pieces like a super-sized 5.56mm. it leaves a mess.
            Info on that study can be found under the Yugoslavian studies, that Fackler footnotes.

          • Fackler’s diagrams show a *much* shorter neck than almost all other military bullets, short enough that you get the extreme yawing even in limb hits, where other rifle bullet have barely started yawing on exit.

            The volume of permanent destruction of a spitzer bullet (especially a long for caliber one) going sideways is considerably larger than the same bullet traveling nose first. With 5.45mm, it’s like comparing a wood chisel stab to a quarter inch drill bit puncture. You’re destroying almost five times the width (maybe 3 or 4 times the volume) at the extremes. That’s significant – yawing that occurs *after* the bullet would be leaving typical human hit is effectively useless. And since skin is much tougher than muscle tissue, you can go ahead and figure at least 3-4″ of gelatine penetration represents the entrance wound, and 3-4″ represents the exit wound.

            Now take into account that the human torso is *not* filled with homogenous muscle tissue, but has gaps in it of mostly lighter structures or voids, and you can see how critical very early yawing or fragmentation is to limb or torso hits – you need that large volume of destroyed tissue *before* the bullet is already waving goodbye, while its still near the chewy, gooey, center.

            The higher soft tissue penetration capabilities sought out for anti-people rounds are more for shots that *don’t* get clean hits, like having to drill an arm and maybe a canteen on the way to the chest. 7n6, M67, M193, M855, and (especially) M855A1 give you enough of both, in most cases.

          • Kivaari

            It needs to hit bone. That’s why I said fluid filled organs, or liver-like composition. Empty bowl get minor wounds, unless full or coincide with a major blood vessel. If our 5.56mm had jacket as tough as the 5.45mm it would not do what it does.

  • Denim doesn’t have any effect on a tumbling FMJ; the denim test is for testing JHP’s to see if they clog.

    His channel has done tests in the past with 5.45 w/ denim and it behaves the same.

    • Zebra Dun

      Well then I guess this is a Kill-O-Zap bullet!

  • Bal256

    I’ve seen gel tests of both 5.56 and 5.45 yaw like crazy. I’ve also seen tests of both rounds practically sailing through in a straight line with far less damage to the block. Better to rely on accurate shots than hollow-points, tumbling, yawing, screw-driving, fragmenting, trocars, or whatever else your miracle bullets are supposed to do.

    • Kivaari

      7.62mm NATO depending on maker is known for punching a straight hole, as if fired from a 9mm or .45 FMJ pistol bullet. US uses 0.008mm thick jackets and the FN uses 0.005mm. The FN loads tend to break apart like the 5.56mm M193.

  • Joshua

    No way is that AR500 and if it is, it is what looks like half the thickness of civilian AR500 we can buy.

    Even M193 can penetrate AR500 plates at close ranges from the M4.

    7n6 is laughable against real ceramic plates.

    • Some Dude

      Maybe so but I would hate to be the guy that took a chestful of 7n24 “super-armor-piercing” in hopes that it would be stopped by a ceramic plate.

      • Joshua

        Same with M995. When it comes to AP rounds only the tungsten carbide penetrator makes it through, and then it just ice picks the target.

        But the key is maximum penetration, and we have the black tip M995 for that and they have 7n24.

  • RICH

    OKAY… ! WAY TO GO A$$HOLE ! ! ! MAKE SURE YOU SEND THIS OUT TO ‘LIBERAL LAND’. I’M SURE THAT THIS WILL BE ANOTHER ROUND THAT THE LIBERALS WILL WANT TO ‘RESTRICT’ US FROM USING ! MAKE SURE YOU FORWARD A COPY OF THIS TO YOUR LIBERAL REPRESENTITIVES SO THAT THEY MAY ALSO ENJOY THE USE OF THIS CALIBER !….. WTF !

    • yeah, how dare someone disseminate information

    • Zachary marrs

      wat

    • Scott P

      They already banned it’s importation, genius. You are over a year too late.

      The “liberals” can’t do anything else to this round unless they get the government to confiscate this ammo which is a huge waste of resources when this round is a tiny, minute, fraction of the overall caliber/ammo market in general. It was never really popular to begin with when more “deadly” calibers are available that are much better known to gun buyers. Plus the importation ban killed what relevance it had even more with people dumping this round in droves.

    • Dan

      They aren’t as clueless as you like to believe, there are enough anti’s out there that do the research for them, much like the pro gun lobby groups supply the right with information. Congressional Representatives are pretty much clueless on all matters until a special interest group get’s in their ear.

  • iksnilol

    I feel so old fashioned for still sticking to 7.62×39 (M67 bullet).

    • Good projo choice in that round. I’ve thought of picking up a case, myself.

      • iksnilol

        It’s the cheapest stuff you can reload. If you are interested in new production Igman makes non-corrosive, boxer primed stuff (about 0.45 USD per round). Is extra nice if you have a bolt-action in the caliber.

        • With the Yugoslavian M67 bullet?

          Frankly, I don’t bother reloading 7.62x39mm. Getting great accuracy out of it is problematic unless you use a .308 barrel and .308 bullets (which means you aren’t really shooting 7.62x39mm; I mean, it will still chamber and fire it, but your barrel life and accuracy are severely compromised when firing milspec M43…), the Kalashnikov design isnt the best choice for super accuracy, and nonreloadable 7.62x39mm is still super cheap (cheaper than reloading it, once you figure the cases in, including both case wear and case loss).

          So, cost is not a reason to reload 7.62x39mm, and performance is an iffy reason with some downside tradeoffs.

          If I want 7.62x39mm type performance, but want to reload for performance, I’ll go with .300BLK. I’ll never get the cost advantage of the cheap steel cased 7.62x39mm, but I have AKs for that, and wouldn’t be driving a .300BLK as a super high volume gun anyway. 😉

          • iksnilol

            With the Yugoslavian bullet indeed. + it is cheaper than the other brass cased stuff I have seen (that and I refuse to buy anything PPU, I won’t support my enemies).

            I like 7.62×39, has the cheapness while also having great potential. You can make good subsonics with it, you can neck it down to the different PPC cartridges, you can make a pseudo Grendel with it. It has a lot of potential. And on its own it is a pretty decent all around gun (best IMO is something like the AK-104). Thinking about it, I really want a bolt action switch barrel chambered for 7.62×39 with a pseudo-grendel barrel for when I want more distance. But I am not a gunsmith, especially not regarding bolt actions.

            It is all about the rifle IMO. The CZ 527 seems good, I have seen sub moa performance from it with factory ammo (Hornady). So I would say that handloading for performance isn’t that worthless.

            The 308 vs 311 conundrum really isn’t a problem. Just have a bit of neck clearance and you should be fine. Shouldn’t hurt accuracy either, at least if you aren’t shooting benchrest or something.

  • Gary Laffoon

    People forget that the Soviet Union came up with this after seeing how our 5.56 round performed. They simply necked down their 7.62×39 round to a .22 caliber to copy what we already had. It ain’t magic, just simple ballistics. A long skinny bullet spin just fast enough to stabilize it will tumble when it hits anything. Spin it faster and it won’t. So your 5.56 toys shot out of a 1 in 7 twist barrel are less likely to tumble than the same round shot in a 1 in 9. Slow the twist enough and everything will tumble.

    • 5.45 is based on a totally new case, not the 7.62×39 case; that is a common misconception.

    • iksnilol

      Uh, if 7.62×39 was necked down to 5.45 you would get .220 Russian.

    • Kivaari

      Soviets were testing this idea before WW2. Many European armies tested intermediate cartridges in the 20s-30s. Even the Swiss were testing “assault rifles” using smaller cartridges.

  • Kivaari

    Each round should have been fired into a fresh block. Multiple hits into already fractured gel, doesn’t give a clear picture. The Army also uses live goats. Sweden uses live hogs. They shoot the critter in the field (and lab), treat it like a person with field medicine, evacuate by a chopper or truck and do repair surgery in field hospitals. Under those conditions, the round is a poor performer.

  • Rob

    One of the worst ballistic test videos I’ve seen. Lots of views of the shooter shooting, very few of actual rounds hitting gel. Next time show the rounds hitting the gel as the focus of the video, and not just shooting. And yes, you will need several targets to shoot…not just replay the impact. …Nice guns though, got to give you that.

  • Erm, fragmentation is an improvement over tumbling. I’m not arguing that M855 is the superior round to 5.45 – it’s clearly not – but it’s a bit strange to say that because M855A1 fragments it’s inferior. It tumbles with a short neck, too, which induces fragmentation. I’m not sure why you think the 7N6 is special in this regard.

  • Kivaari

    Our SOF folks use quite a bit of heavy loads, with bullets of 69 to 77 grain. They give better accuracy while keeping lethality at longer ranges. The primary reason the Soviets went to the 5.45mm is the 7.62x39mm is short range and has a more limited ability to wound.
    With the AK74 the Soviet or Russian soldier has improved his chances of hitting his target by 2.5 times that of an AKM.

  • iksnilol

    I thought they included the rounds fired in training in the 250k figure?