I haven't seen a test with ceramic. Stops it?

You needed to do that anyway.

Kind of an example.

Maybe a dumb question, but why would solid copper be harder on a barrel than copper jacketed?

Not as squeezy?



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Nope. Not if they declare it "armor piercing".

77gr Sierra TMKs.

Doesn't mimic it's terminal ballistics.

I'm thinking more of a civilian context if this ammo becomes available in the future. Civilians don't have the budget and taxpayer dollars to be replacing barrels and such frequently; not most of them, anyways, and to an extent this extends to civilian law enforcement, too.

I'm just thinking of trajectory for practice; also curious about an equivalent for M80A1.

Yes, it's not so much the jacket as the core. Solid copper core are harder thanrad from what I understand

Peasant ar500 armor clad dirt shooters will now be as obsolete as we all knew they always were!

Thought I read it was shooting at like 5 moa plus.

They fined the Army... For using lead ammunition?

Are you fucking kidding me? Just- how?

As far as I'm aware, the Army can tell any regulating agency to go fuck itself with impunity. What the fuck?

I want to try some m80a1 pulls in my 300blk.

Not true at all

You will not see this ammo being sold in any manner of surplus (to include pulls, rejects) to civilians or anyone else. We will not share it with our NATO partners, to include the FVEY ones, if that tells you anything. We have gone to great lengths to prevent its leakage in theater and anytime it's found there is a serious investigation to determine source, quantity, etc. The US views this as providing a qualitative edge in performance over other ammunition and does not want anyone else getting their hands on it.

Oh, I've said this before but the pressure of the ammo has been brought down in subsequent batches to where it matches that of M855, along with the ballistic trajectory. The round wasn't destroying feed ramps but it did leave a dimple. It does the same on the M249 and M240 (with M80A1) but I'm not aware of a program to modify either weapon to prevent it, so I don't think it's considered a serious issue.

Well, that's just plain cross-eye retarded. And if the EPA is harassing the Army, then the EPA needs to get its pee-pee smacked, hard. Anyone else think they ought to be defunded?

Nothing personal, but BS on all counts.

You can't have a charge weight of WC846 that's two full grains heavier than M855 and keep the same pressures. It might be possible if you had a bullet with dramatically reduced bearing surface, but that would be plainly visible in the bullet design, and velocity would drop, thereby rendering a reduced terminal effect. The bullet has not had a bearing surface or ogive change, and remains a higher BC bullet leaving at a higher speed, so the trajectory cannot match - its mathematically impossible to do so, unless you drop the charge weight or change propellants outright, which again would render a reduced terminal effect than originally advertised. That brings us to the topic of armor penetration that the Army is so hell-bent on (and range overmatch, but that's another story that can be seen from both sides of the fence). It completely foregoes the concept of combined arms, and the availability of M995 (DODIC AA69).

Regarding the receiver ramp damage, they (perhaps that means you all) are on the 7th magazine design with a follower that was blatantly ripped off from Magpul with enough of a deviation to avoid patent infringement, and a feed lip re-work that is curiously close to that of the PMag. If it wasn't a serious issue, why would the Army fully field one magazine, call a stop-issue order, and re-issue a completely different one (there's contracting shenanigans here), one that's twice the price of a standard USGI magazine, and about two to three dollars more than the M3 PMag? It was a rather large problem, and it was rendering weapons completely unreliable early in their lifespan.

I'm not saying that the EPR bullet is inherently bad. I'm not saying that better terminal performance on soft targets and better light armor penetration is bad. I'm not saying that the lead-free SOST is the answer. What I'm saying is that the green-range/ammo initiative is tens of millions of dollars in the hole, weapons are breaking bolts like candy, toasting barrels and bolt gas rings, and killing extractors, actual pressures have been actively hidden by the Army, and the program is a giant 'too big to fail' SNAFU reminiscent of the days of a consolidated Army Ordnance. Their blatant mismanagement of the program, false advertising and information campaign, and more is borderline criminal. If Congress actually chooses M855A1 as the standard DoD cartridge, I hope they stub their pinkie toes every hour of the day, every day, on the hardest piece of furniture available, for the rest of their lives. I wish worse upon the EPA. I wish the EPA folks who are pushing the lead-free thing go to my version of hell - where you have to walk across a lake of Legos for the rest of eternity.

S/F

Yes, these are only level three ceramic plates.
Though to be fair steel body armor has been obsolete for quite a while now.

Yet the peasants still line up to buy that shit.

Feeling pretty good about my Level 4 Ceramics now. Finally a justification!

Fuckin' Bravo.
I've seen semi-oblique reference to M855A1 "EPR" producing pressures that approach 5.56mm proof-load levels. No first-hand documentation though, because as you said, the Army is doing the best "Don't look behind that curtain!" it can on the actual or possible negatives to the Green/EPR ammo fielding.

So practice with something nicer to equipment? It was designed to mimic M855, not sure how close it actually does.

Civilians also don't shoot that much, and if they do, it's because they've specifically decided to source and shoot this ammo. How many people (even here) give positive reviews on 100 rounds fired?

American Rifleman has an article from June 2014 that stated that the round was more accurate out of a 1/9 barrel and they said M855 was more accurate as well. I know 1/7 was adopted because tracers could only be stabilized out of that barrel.

This logic makes no sense to me. Who is firing tracers out of M4s and why are the manufacturers and we the buying public sucking up on the 1/7 twist barrel?

Sorry to be tardy to the party, but I thought the A1 was AP since it was like tungsten or cobalt or something?

It's a steel penetrator atop a lead free bullet

Weren't some of the early runs done with bullets considered to be AP?

Anyone want to send me a scale to measure bullet powder? I can get down to how much powder is actually in M855A1 in a second, as I have a magazine full of the stuff.

The part in eed is completely incorrect.  One of the big benefits of the M855A1 is higher velocity, which results in higher peessure levels.
The pressure levels and ballistics have not changed.

The "dimple" in the feed ramp is enough to catch the tip of the bullet and cause almost continual stoppages after a few thousand rounds, but the new tan mags mostly fix the problem.

It's not approaching it, it's actually higher than the proof pressure at triple digit temperatures

Per the article the powder is not WC 846 in the A1 round it is St Marks SMP 842

According to a DTIC presentation from General Dynamics St Marks SMP 842 can produce a velocity of 3,020fps at 54,200PSI.

Also this is according to what I know the powder used in M855A1.

This is in comparison of M855 loaded with WC 844 with a velocity of 3,020 fps at 55,000PSI.

However don't let facts get in the way of M855A1 bashing. I thought it was common knowledge M855A1 used SMP-842.

Superformance!

Probably not exactly Superformance, but that's who makes it and who started the trend in higher performance ammunition with Light Magnum years ago.

Army herped and derped hard on M855A1.

They went full M4. And now the USMC has followed, along with pretty much everyone else. Then they piss and moan because, surprise surprise; the M855 doesn't perform as well in short barrels.

Solution: Make a round that is going to beat the living piss out of our carbines and cause maintenance costs to skyrocket, along with the costs of the new round itself. Because fuck the A4 and M855, that wasn't good enough.

And if you think that we'll always have CAS/arty on demand in every future war, you're fucking high. That's a luxury as soon as we start scrapping with another modern military adversary again.

This is a folly brought on by thinking that we will never fight a conventional war ever again, and everything is going to be insurgencies in built up areas from here on out.

The loss of rifle marksmanship is going to hurt us in the end.

You can keep that shit. I don't care if it comes to the civilian market or not. My guns ain't going to be eating it.

This is correct.
We have used quite a bit of the 842 that was pulled down from the early runs of 855A1.
Great powder, has CFE in it.

You're telling me M855A1 is pushing chamber pressures higher than 70,000PSI?

Also I ordered a reloading scale so I will get to the bottom of this! I'll pull one of my M855A1 rounds and measure the powder and we can see just how many grains of SMP-842 it is loaded with.

Those velocities are out of a 20" test barrel comparing the two powders.  That is NOT what  M855A1 is loaded to.  It is getting almost 3000 fps out of a 14.5" barrel, and the resulting pressure is above 60ksi

Yes, at temperatures that could easily be obtained by leaving a magazine laying in the sun.

They are working a a higher pressure proof round now because of it, but it's pushing the edge of the gun design so the new proof won't have as high of a % of over pressure.

You are correct, however M855 achieves around 2,830fps from a 14.5" barrel with a chamber pressure of 55,00psi.

If SMP-842(not WC846 like was said) can achieve 2,830FPS with a 62gr round at 54,200PSI, I don't imagine you would need to add 7,000+ psi chamber pressure to eek out an extra 170fps.

Like I said I'll find out by Wednesday when my scale gets here and I pull and measure the powder load. I'd like to prove it, since y'all were getting the powder used wrong you could be mistaken on other aspects.

What scale did you get?

Government agencies are not immune from government regulations, especially when it comes to contamination of ground water and rivers. Some of the largest and most expensive superfund sites are government operations. And if you actually read the summary of the action, it's about allowing copper and lead tainted soil to run off into a river, AND not reporting it IAW regulations.

Alright groupie, put your thinking cap on. I was in fact mistaken on the powder, as I do deal with a lot of ammunition matters on a routine basis, but I am not mistaken in knowing advertised pressure specs are lower than reality.

Let's make two scenarios and discuss the implications of each, and why measuring the powder charge is an exercise in futility. Scenario one, the following reference is in fact wrong and SMP842 is used. Scenario two, the following reference is in fact correct.

Reference 1



Reference 2



Scenario 1 : Assuming SMP842 was used, this would mean that the formal Army marksmanship publication (reference 2 )is in error either by mistake or by design. This would also mean that there is, yet again, another powder change at the tail end of a 19 million dollar program - that [M855A1] would be a hallmark of fraud and waste. Its a rifle cartridge, not a TOW missile, and this isn't that difficult to fix. Yet the Army can't get a uniform, Bradley glorified taxi, or ammunition right, and frankly rarely has been able to (the M4A1 being a rare example of a good move). This would also assume that with the new powder, in order to drop chamber pressures roughly 10,000 PSI, that velocity would have to be dropped, yielding reduced terminal effect as advertised. A simple change in powder with such similar burn rates (reference 1) will not EVER drop 10,000 PSI unless another factor changes. It is physically impossible, unless the charge weight was dropped and the extra velocity gain is being advertised from a 20" EPVAT barrel, which is deliberately misleading. If there has in fact been a final propellant change, either the chamber pressures or advertised velocity/terminal effect is fictitious. Again, this is borderline criminal.

Scenario 2: Assuming WC844 was used, this would mean that the formal Army marksmanship publication (reference 2) is in fact vetted and correct. Furthermore, this means that either the chamber pressures or velocity is fictitious. As M855A1 has been chronographed, this leaves chamber pressures as suspect at best. We also know through ballistic tests that the bullet is not in fact barrier blind, which leads us to conclude that the Army is hell-bent on a 600M capability and or armor penetration capability, which we know to be true. This deliberately overlooks the concept of combined arms, and is pushing the platform to beyond what is is capable of handling. This is why weapons are breaking all over the place, something the Army can't quite hide.

Individual Analysis: If you are to pull a bullet and weigh powder, you likely have no way at home to know what powder you are weighing, even though the actual charge weight would be neat to see. It is important to note that charge weights of military ammunition fluctuate depending on lot, and are selected through pressure tests - whatever number you come up with will not tell you a whole lot. Visual inspection is not enough to draw a solid conclusion. You also don't know when that ammunition was produced, as many types of ammunition were charged with SMP-family powders at one point, whether to test or field - even the vaunted Mk262 (it does not have SMP within). This brings up another question - where are you sourcing this ammunition you have? Gunbroker? Where are those individuals getting it from? Assuming the unlikely case they got it from legal channels, do they know when it was produced?

If you wish to do something that will yield real data, find someone with an EPVAT or other pressure test barrel, and shoot some of that ammunition. You would be absolutely amazed at how quickly chamber pressures stack up when trying to attain high velocities from a 14.5" Colt or FN barrel. Finding an extra 170 FPS can be a big deal, and in the long run isn't worth it.

S/F

But it can take like a hundred hits bro and it's cheaper.
Don't worry that M193 completely butters it.

Ceramic fags btfo.

It's Scenario #1, and while their are numerous issues with M855A1 misadvertising, this one may not be as nefarious as you make it seem.

In general the FM writers don't talk much to the Tech community. Specs and operational/maintenance instructions frequently are contradictory to actual performance and those found in the TMs.

In this case the training pub is just wrong.  The probably just copied and pasted the m855 specs.

The powder is SMP-842, and every official news release states the pressure is higher.  Various sources online have stated either 62 or 63ksi @70F.