5.56mm M855 in a

[@ftdefiance1]

I can't speak to the heavier 5.56 ammo. The 55 grain ammo out of an iron sighted 20 inch at is extremely impressive. I was issued the A1 and limitation was my eyesight.

[@angry_zergling]

Yep - my AR-15 has always been more accurate than I am out to a further range than I can reliably shoot.

[@madd-mattmitchell917]

Actually, well done sir! It was an unexpected result, however, a little "eye opening" as it were. Thanks for putting this up! I also am a huge fan of the "retro" rifles with a BRN-Proto and two of the early models ( 601 and a 604) in my tool box as well. Thanks again!

[@Marcus2750-u1t]

I would love to see this test at longer ranges.... 100 yards, 200 yards etc.... thank you for the content !!

[@7N6ballistics]

I don’t think I would be able to hit something that small at distance...its more of a close range thing. As far as destabilizing....it isn’t going to matter...its not fully stable in the first place..

[@rangercal1]

Thank you I've been waiting years for someone to try 1/12 with 62 grain.

[@angry_zergling]

1:7 was chosen to stabilize the 62 grain tracers because those things are about as long (it's projectile length not weight that determines stabilization - for anyone else who didn't know that for a long time) as an 80 grain lead core. Adopted 1:7 when they went from M196 tracers to M856 tracers. Turned out to be a happy coincidence that and 77-grainers became in vogue that's 1:7s slang most of them pretty good.. A tight 1:10 would be good for most non-monolithic copper 62-69. 1:8 is good for sub >80 lead core. But those darn tracers are tall boys and need that 1:7...supposedly. Never tried,

[@Hwuoow]

Would be great to see a comparison of m193 in a 1:7 and 1:12. Especially out of a 20 inch barrel.

[@7N6ballistics]

Thats pretty well documented...with a properly stabilized projectile there isn’t any noticeable difference. About 4-5”of neck and within 150yds or so, lots of fragmentation.... The problem with m855 is there are 3 different wound profiles. The most common being about 4-5” before it begins to upset....sometimes it can be closer to 3”...others as much as 8”....it’s inconsistent.

[@corycarlson8712]

I bet a 77gr out of a 1/9 would do the same thing. Awesome video!

[@7N6ballistics]

Very possible...but the 77gr projectiles dont seem to suffer from the inconsistent terminal performance as M855. That said...in a pinch... I don’t have a 1:9 to test though.

[@alanhelgeson690]

Eugene Stoner designed the AR-15 with a 1:14 rifling twist rate which just barely stabilize the 55 grains full metal jacket M-193 round at normal temperature.. the rifle was tested by the United States military in Alaska and the cold winter air temperature which is denser than warm air temperature, the 1:14 rifling twist rate would not stabilize the 55 grains M-193 round so the United States Military' insisted that Armalite change the rifling twist rate to 1:12 which stabilize the 55 grains full metal jacket M-193 round in the Arctic climate. The slower twist rate is much more lethal weapon than the faster twist rate. If you decide to go with a heavier bullet weight like a 75 - 77 grains you would probably have to go with a 1:9 twist rate. However the 55 grains ammo is a lot cheaper than the heavier bullet weight.

[@chrischiampo7647]

Nice Test I Was Curious Myself 😀😊👍🏼 Thanks

[@awsomedude9111]

really like this topic because I'm realizing from videos that a lower twist rate is like trying to catch a football without spin and when you catch it it jumps out of your hands.

[@awsomedude9111]

also wondering about 1:14, but would be cool to see exact same length of barrel 1:12/14 vs 1:7/9 in 55 gr FMJ For an example 14.5/20" barrel with 1:14/1:7. To test overall damage watermelons and/or pumpkins would be good.

[@7N6ballistics]

Kinda…

[@AA-dn8dj]

I heard that 1:12 was made for the original 55 grain FMJ M193 and 54 grain M194 tracers, and that 1:9 was made for the M856 64 grain tracer and 62 grain M855 FMJ, but that 1:9 was abandoned for 1:7 as it did much better with 64 grain M856 and later heavy grain ammo.

[@7N6ballistics]

Yes, 1:9 was needed for the SS109 projectile...it was the M856 tracer that required 1:7. For instance, the FAMAS G2 uses 1:9...I can only assume whatever tracer round France uses is not as long as our M856.

[@AA-dn8dj]

@@7N6ballistics Oh I see. I knew what I said before from conjecture and comments, nice to have that clarified. Doesn't the earlier model FAMAS only take .223 pressure loads?

[@7N6ballistics]

@@AA-dn8dj It uses a steel cased round....im not sure exactly on the pressure specs.

[@olysean92]

Excellent video and info for sure. I would love to see an episode testing CMMG Bravo 22lr conversion in that 1:12. My 1:7 is sub MOA with 77gr Norma Match. It's 9 MOA with 40gr CCI MiniMags.

[@7N6ballistics]

Its entirely possible that rate of twist is too high for that projectile...

[@olysean92]

@@7N6ballistics I'm assuming that is the problem. Still tons of cheap fun on 5" steel at 50 yds. But I'll bet your 1:12 will shrink that group a bunch.

[@7N6ballistics]

@@olysean92 possibly..but I do not have said conversation kit.

[@timbango2090]

Please someone do a video with a brick wall. With this 1:12 twist green tips vs 1:7 twist. And maybe throw in the 7.62x39. I'd like to see the 1:7 twist vs 7.62x39 on a brick wall like we always do. Then see if green tip 1:12 gets closer destruction to the 7.62x39.

[@propdoctor21564]

Great video 😁😁 I love this stuff

[@chrisrayburn]

In the 1:12 do the holes lokk keyholed m855 should destabilize bad and give a keyhole or water drop look. That's why I don't buy green tip at all I stick to m 193 1:7 twist. For my fmj

[@dalanwanbdiska6542]

Norinco jw 105 5.56*45 nato has a 20 inch 1/12 twist chrome lined barrel so it shoots best with 55 grain bullets. I use 556 or 223 . I have a 4x wide angle 32 mm tube scope and it needed the medium rings for the bolt handle to not hit , look high like the ar 15 sights. Id love to zero this @300 meters for +3 inches @100 meters but the snow is past knee deep and its melting now so in afew weeks i can zero it in my shooting range, field. Im bedding the stock full bed up to past 1 inch of the barrel lug for a free floated barrel. Jb weld and neutral shoe polish work excellent. Im redoing the color of the stain and the finish, maybe tung and teak oil for a non-shiny waterproof finish. My buddy has a bunch of bullets for me , he gave me a handful last tine and I shot those up when the rifle had the tube style reddot sight , zeroed for far range at 75 meters and close range 25 meters. These bullets shoot super fast and hit the target @ 100 meters instantly. I love the 556 nato round now. I was always into 7.62*39 but now I can shoot both. Bolt action 556 is a pretty slick little rifle. Take it out for some gophers this summer time.

[@bobbyc2768]

A 62 grain lead core jacketed bullet would be fine for the 1 in 12 twist, you said up to 60 for lead core. The reason m855 isn't good to go in 1 in 12 twist is because it isn't just a jacketed lead core it obviously has the steel core so to make it 62 grains it has to be longer than something with just a lead bullet wrapped in copper would be of the same weight.

[@7N6ballistics]

Well…I said “about”. The video was about specifically “green tip”. Different projectiles will have different length to weight ratios…such as monolithic projectiles, polymer tipped projectiles, hollow point boat tail and so on. Id imagine even the 64gr nosler bonded could be used do to its profile…. That said velocity, temp, altitude etc…will probably come into effect and it would be wise to always test your ammo in your gun in the conditions you plan to shoot if you are going to exceed approximately 60grs with a 1-12 twist.

[@alanhelgeson690]

Actually the length of the bullet in regards to the bullet's diameter is more important than the weight of the bullet. So if you are interested in getting a accurate understanding you really need to know the exact overall length of the bullet so a micrometer is needed to accurately measure the overall length of the bullet.

[@gizmo8760]

Hmmm...I haven't seen barrels with a 1:12 twist. Not that I would want to buy one. Mine are all 1:7 and 1:8.

[@7N6ballistics]

Its a recent thing..because of the retro movement...

[@dbmail545]

My 1t:9" Bushmaster would stabilize 77gr pills, but would not group as tight as 1t:7"

[@7N6ballistics]

Ya, 1:8 is required for proper stabilization of 77gr in all conditions.

[@alanhelgeson690]

It All depends on what you find to be more desirable quality accuracy or lethality. If you are only going to be punching holes in paper target then you are probably concerned more with accuracy. If you are more interested in lethality the you want a bullet that is barely stabilize so that it Will tumble end over end Length wise dumping all of the bullet kenitic energy into the Target.

[@Marcus2750-u1t]

The slower twist lends itself great to lighter pills like a 40 grainer running almost 4k fps with hand loads 👍🏻👍🏻👍🏻😬😬😬

[@Marcus2750-u1t]

@Marino yes same here, I have a 24” .936 bull barrel that Ive shot over my chrono at barely shy of 4k...... moving!!!

[@rollymarasiganreyes4950]

Nice video😊😊😊

[@AlexJay3211]

So is the Armson website the best price for that OEG?

[@7N6ballistics]

Not sure

[@UrbanTiger74]

Yeaaaaaa boiiii....The OEG.

[@7N6ballistics]

OG haha

[@AA-dn8dj]

M193 is perfectly fine from 1:7 rifles though right?

[@7N6ballistics]

Yup. You might get better accuracy from 1:12...but it is perfectly functional in 1:7

[@AA-dn8dj]

@@7N6ballistics Awesome thank you 7n6. I just prefer using one all around twist rate for my uppers. I like to load my mags staggered sometimes with different grain ammo for fun.

[@dbmail545]

There is a phenomenon called over-stabilization. If the pill is spinning too slow it will keyhole and fail to aerostabilize. If spinning too fast it will fail to aerostabilize as it starts to fall to earth. 1:7" barrels are notorious for the m193 going amok past 400m. Check out 9-hole reviews and the poor downrange performance they get out of m193 in 1:7" tubes.

[@7N6ballistics]

@@dbmail545 thats possible...but the m193 was never known for good accuracy past 400yds...that was a complaint even when the 1:12 was standard.

[@AA-dn8dj]

true true, m193 does vere off into wind past 300 yards. it's just a cartridge limitation.

[@williamdunford2008]

good info!

[@TheMrwhite6199]

M855 IS HORRIBLE AMMO....tHE WORST AMMO YOU CAN PURCHASE

[@Dcm193]

The fort scott tui is the worst .

[@HaventHeard307]

What's that ringing?

[@7N6ballistics]

Original 3 prong flash hider.

[@HaventHeard307]

@@7N6ballistics sounds like a tuning fork lol, thanks.

[@7N6ballistics]

Yup

[@Agiel_Catering_Kebumen]

Nice video 👍☺️👍☺️

[@travhammer]

U will not have good results. . I hope u have an. 5 56 chamber.

[@7N6ballistics]

I am unaware of anyone using a .223 chamber spec in ARs…or any semi auto these days. The results were actually better than expected.

[@travhammer]

@@7N6ballistics there are several

[@7N6ballistics]

@@travhammer who?

[@travhammer]

@@7N6ballistics use ur 7n6 and research. One clue of four, H

[@Edmondson_Avenue]

Everyone always screaming don't fire a 5.56 in a .223 barrel and I call bullshit because the original AR-15 adopted and redesignated as XM16E1 and M16's had .223 barrels and there's no documented evidence of firing a 5.56 ammunition in a .223 barrel will cause chamber explosion, the M16A2 chamber was designed to be loose to help with extraction issues that the AR-15 603/604 XM16E1/M16/ M16A1 .223 chambers had, the .223 chamber has tighter tolerances, so the M16A2 has the first 5.56 dedicated chamber with looser tolerances like a Glock barrel it allows the case to expand some for more easier extractions but it gives up some accuracy. 5.56x45mm "NATO" was not around during the Vietnam war, 5.56x45mm "NATO" didn't come about until 1976 or 77, it was designed FN Herstal in Belgium, so anything before this round was created was .223 Remington M193 ball ammunition also at the time called 5.56x45mm but not 5.56x45mm "NATO" their a difference, but a lot of people push lies saying that "firing 5.56x45mm "NATO" in a .223 AR-15 is dangerous because 5.56x45mm "NATO" has high pressures and could lead to catastrophic failure" I say horse shit 🐎💩 because you have people who have been firing FN 5.56x45mm "NATO" ammunition like M855 in their AR-15's that predates 1982 which the M16A2 chamber pattern AR-15's were created and introduced, and here's a quote from a forum "The M855 will chamber and fire in the M16A1 safely but accuracy is seriously degraded. It is approved for use in the M16A1 only in a combat emergency and it is only accurate to about 100 meters. This is combat accuracy not, benchrest accuracy." So FN's 5.56x45mm "NATO" Cartridges like SS109 and M855 wasn't used until the summer 1982 when the M16A2 was adopted by the U.S. Marine Corps and FN SAW M249 adopted in 1984. So if 5.56x45mm "NATO" is ok to fire out of an M16 and M16A1 with the only concerns is accuracy because the M855 was designed a 1:7 twist ratio and the M16 and M16A1 have a 1:12 and 1:9 twist ratio but their's nothing saying M855 will blow up a M16 and M16A1 's chamber, and all the people over the years who've fired 5.56x45mm NATO ammunition out their AR-15 rifles which prepredates the 1982 M16A2 variants which were designed for FN 5.56x45mm NATO ammunition and the M16A2 has a looser chamber

[@7N6ballistics]

I….uh…ok. I don’t think anyone was concerned with blowing up their AR…This video was about the 1/12” twist and m855…or simply the SS109 projectile in a 1/12” barrel.

[@Edmondson_Avenue]

@@7N6ballistics I was just making a point, my comment is random and not towards you it's for those who say don't fire 5.56 ammunition out of a .223 barrel, but my point is that 5.56x45mm NATO wasn't invented until the late 70's but people always bring up don't shoot 5.56 out of a .223 gun but the M16A2 and M16 are chamber for .223 Remington M193 they predate 5.56 NATO ammunition, but people still fire M855 out of M16A1 and AR-15's patterned after the M16A1.

[@7N6ballistics]

@@Edmondson_Avenue While I do not own any .223 chambered rifles, thus not a concern of mine, SAAMI released it’s warning about firing 5.56 military ammo in commercial .223 chambered rifles in 1979. This predates the NATO adoption and was not referred to as 5.56 NATO…but simply 5.56mm. M193 has always been referred to as 5.56mm and had it’s own specs with allowable pressure and case composition being different than .223. As far as chambers, the military again has it’s own TDP. Whether or not 5.56 NATO was simply renaming what was before simply the US Military TDP, I am unsure. As far as the concern, I don’t know of many rifles outside of maybe bolt or single shot rifles that use a .223 chambering. I believe the 1980’s Ruger mini-14 may have, but I don’t recall any of recent times. I would have to think a bolt gun would do a much better job of preventing primer blow outs or case ruptures from occurring. This may be why you don’t here of any real issues occurring. That said the major manufacturers do have different product lines loaded to different specs. Here is Hornady’s explanation. www.hornadyle.com/resources/le-faq/what-is-the-difference-between-556-nato-and-223-rem-ammunition If you want a lengthy read on the development of the M16 and 5.56mm here is a link. You will see there were a lot of issues to include case ruptures and cyclic rates that were encountered early on. In short the M16 and subsequent 5.56mm rifles were designed around the 5.56 specs…. There is no way of knowing how a commercial firearm marked .223 would fair…which is likely a reasonable reason for the warning. web.archive.org/web/20040209030852/www.thegunzone.com/556dw.html

[@Edmondson_Avenue]

@@7N6ballistics Well said, but there's manufacturs rolling M193 5.56x45mm NATO, when it was traditionally Remington .223 redesignated 5.56x45mm M193, I was reading that the military allowed M855 to be fired out of M16A1's which predates 1979 but only for emergencies but not over chamber pressures but because of poor stability, the M16A1's 1:12 twist ratio can't stabilize 62gr. projectiles past 100 yards. You know it's weird that some .223 ammunition that's hotter than 5.56x45mm NATO, but I was watching a Brownells video and a guy was explaining that SAAMI says 5.56 NATO has a wide pressure variation to work in all NATO weapons, don't quote me bit I think he even said that some .223 cartridge could be to hot for some .223 chamber and cause failure. You this leads me to believe that early variants of .223 wasn't studied enough on the civilian side, because it was originally a military cartridge from jump starting out as the Remington .222 and the first gun it was chambered for was the AR-15, I've heard similar stories about .30-06 ammo blowing up guns, I think a lot of it is the manufacturer of the firearms not making good chambers, because I've also read and seen videos about companies that manufactures .223 rifles with .223 barrel marks but their manual says it 5.56x45mm NATO rated and ok to fire 5.56 NATO. It's like 10mm, which is designed to be a magnum cartridge but you have a lot of ammunition companies producing watered down loads and some gun companies making poor guns after firing a lot of the real deal ammo the gun fails, because it was really designed for those 10mm lite .40 loads, there's a lot of misleading.

[@7N6ballistics]

@@Edmondson_Avenue pretty much…5.56 military loadings can be whatever they specify..m193 was allowed to be loaded to higher pressure than .223 and was allowed as much as 60,000 psi…this is why it isn’t an issue shooting m855 in the A1. The bottom line is 5.56 can exceed .223 pressures…and when placed in a short chamber along with an unknown quality of rifle…I could see where the concern would have merit…thus the warnings. As to whether or not it’s a wide spread issue..probably not, but I am sure kabooms have occurred that go unrecorded…