I want to star this by saying this is far from scientific. I only have 30 rounds of M855A1 and I am hesitant to take sharpie to my feed ramps and run these rounds at the range. Maybe I will eventually, but as of now the ammo is just a bit to rare and it cost me far to much to run it at the moment.

So this is what I have, It's not scientific but it is a half way decent demonstrator of the angle magazines feed M855A1 into the feed ramps. These are best case scenarios, and if you ran these in a high cycling gun the steel tip would strike even lower on the feed ramp as the round will not have had time to be fully pushed up into the magazine.

Tan follower Brownells GI mag: This one is practically laughable, even under the absolute best case scenario it barely makes it to the steel feed ramp. In a high cyclic rate firearm it's no wonder the Army is having issues with M855A1 tearing up the M4 cut feed ramps.


Lancer L5AWM: Better than the GI mag of course, not what I would consider ideal though. Lancer makes good mags no doubt but the feed angle could be better. It makes it to the steel ramps, but I would be hesitant to see how well it works under a high cyclic rate.


Tangodown ARC Mk.2: Good feed angle that allows for a wide margin of error in cyclic rate and round presentation.


Magpul Pmag M3: Another good feed angle that allows for a range of round presentation without having to worry about the aluminum feed ramp cut. However M3's seem to have a super annoying transposition of the second round.


ETS Group: By far the best feed angle of the magazines I have available. Avoids transposition of the second round and offers the widest margin of error.


So there you go. Those are the mags I have, I wish I had more brands and I wish I had more rounds to do better testing. This is what I can offer however and hopefully it sheds some light on magazines with M855A1.

Pmag M2: On par with the M3.

I'm super hopeful this is indeed the case, I like Pmags and Magpul in general, but the Gen M3 has been a problem.  I am giving them a really big second chance right now though.  

I just got my hands on a new set of 6 Gen M3s that were from a case that was packed this month, date wheel on the mags show they were made last month, 10/15.  They have the nubs inside the lips and it is pretty much impossible to get the second round to cross up with the top one.  

The polymer seems stiffer than some 2013 manufacture M2s and M3s I have, but that's just going by feel.  

Cool.  

Is there any disadvantages that y'all noticed since implementing the nubs inside the feedlips?

Do the new sand 40 round M3 mags have the ribs that the new sand 30 round M3 mags have?

I hope so. Wish I had the ammo to do sharpie tests and live fire so we could get an idea of how they feed when the rifle is being run fast.

so is it just the follower that changes the angle?

Feedlips.  

Page 4 has an image of the improvements.

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CCIQFjABahUKEwjL2L3Y-pLJAhVWMYgKHevUCcg&url=http%3A%2F%2Fwww.dtic.mil%2Fndia%2F2014armaments%2FWedLucas.pdf&usg=AFQjCNEPPRfjEyWktcfwhWXRlcTTo6muJw



The grey parts are the improvements over the original orange part.

Note the elevated feed lips.

I'm somewhat interested in the new g.i. mag redesign, but in all reality, Magpul has been doing that for about 8 years now.

A group that I'm involved with has been looking at mags and they were down to Brownells tan follower mags or Gen M3 Pmags.  We got a distributor that would pull the very newest stock of Gen M3s and they went with those on my recommendation and I'm not the world's biggest Pmag fanboy, but they do feed well, they are compatible with the 416, and they are plenty cheap enough (purchased by the case with LE discount).  

IMO, the military should give credit where it's due, save some money and use Pmags.

Added the Pmag M2.

Should I use black sharpie or fingernail polish to paint my feedramps to live cycle a round for a bit better test?

Is there really that much area of adjustment available to change the angle without the carrier dragging on mag lips or the bolt riding over the back of the cartridge?

Just for everyone here I went ahead and tested one of the rounds with live feeding.

I painted the feed ramp with white out and ran the round 3 times from the bolt open position to get a decent view of how it hits the feed ramp when being fed from a fully loaded 30 round magazine(29 on the Pmag and Lancer to get the round of the left side).

Pmag M3: Perfect feed angle, by dropping it with the bolt release you can see the round barely meets the feed ramp and completely avoids the aluminum upper.


Brownells Tan Follower GI Magazine: Again just laughable, just barely passes the aluminum upper and would most certainly strike it during full auto fire.


Lancer L5AWM: Not looking to good, seems to have a similar feed pattern to the Tan Follower GI mag. Image isn't the greatest but the black line in the center is what you seek.


ETS Group: Another superb feed pattern. Sorry for the blurry photo, my mag seems to feed a bit to the right instead of more centered so I had to work my phone camera to get the wear patter in the white out. Still far above the aluminum upper.

I don't recall hearing of any issues with it when we were in Afghanistan in 2010 with this ammo. Not sure how long it had been fielded at that point though. Most of us were using issue magazines, some had Pmags at the time and one guy had a 100 round beta until he was told he couldn't use it anymore and to leave it in his tent. And yes we fired our weapons, a lot......hmm on second thought I did have a issue with feeding the first round in my M16A2 about 3/4 of the time or worse I had to charge it twice/ pull the bolt back and let it go twice to chamber the first round, most guys had M4's and didn't seem to have the problem. Rifle ran fine other than that initial feed issue. I was using issue magazines, don't recall what follower was in it.









P.S. Fuck Gormach.

In the OP, why are the first two pics taken with the cartridges further back than the rest of the photos? The gap from the rear of the mag to the rear of the cartridge looks to be only half what the others appear to be.

Have you tried any live fire, and had problems or wear on the upper?

Not the OP but the cases are further back because the bullet hits the ramp sooner.

Further back because I stopped them where the bullet tip first strikes the feed ramps.

As you can see from my white out test, the GI mags and Lancer L5AWM mags have the rounds strike the feed ramp at the base of the barrel extension and just slightly above the aluminum upper receiver cuts. This is bad given that the steel tip is much harder than the aluminum upper. Also I wish I could live fire them, I have 30 rounds which cost me a significant sum. To see any noticeable wear I would need about 5,000 rounds for each magazine brand.

I don't have that nor could I afford it, so I offered the best I could with what I had. It's still more than can be found openly anywhere else about how to avoid the known damage to the upper receiver M855A1 causes with certain brands of magazines.

Very good informative report and great thread!...Concerning the US GI  brown follower magazines,  just one of the many issues with them. (Last round on the left counter to almost every other mag on the planet. Reduced life cycle I have seen more double feeds the last two years than any other magazine.) If you dont use or don't have access to ETS, Magpul or lancer mags, then the older Green follower GI mags are way better than the so called improved brown follower mags.    

M855A1 tearing up feeds ramps yes on the military side of the house there are reports. Im lucky I run mostly MK262.


My current go to mags:  IMI, Magpul Emags, Older IMI, BCM and Lancer.

That's weird.   I've been using the tan follower mags for five years and had zero issues with 'em.  I've been impressed with 'em.

Wow - interesting read.

So, do i understand  this correctly, that a new environmentally sensitive round has been adopted that is unreliable with untold millions of mags that have been issued over the last 50 years?  

I like your photos, but I have a question. The rounds that are feeding well are way further forward in the magazine itself. Why are they so much further forward?

What was tested in this thread was the brown follower mag, it is the third military mag since the 1980's. First the Black follower (no anti-tilt properties) Green follower   some-anti tilt used from about 1997 until around 2012,Brown follower   last round sits on the left, supposed to be improved over green follower and better for the Iraq / A-stan environment. ( I would say no.)

 Also here is some real goodness... You think going with ammo that is not good for our guns and mags is bad. Most military shoot houses are not M855A1 capable so we went with a round we cannot train with! And its hell on steel, so no steel shooting either if you want your plates to last!

What's scary about this pic, I found this black follower mag down range in Afghanistan. Nothing like being given a 20 year old mag to trust your life with.
(No I don't use it!)

I stopped them with they first strike the feed ramp.

The mags that feed ideally for M855A1 strike the ramp farther up so they of course are farther out of the mag than those striking near the very bottom of the feed ramp.

From what I have found, Pmag and ETS mags are the ideal M855A1 mag.

Stukas87,

I have some questions:
1. Are you suggesting that the previous gen mags will not have the problem that the tan follower mags do?  If so, then why would they redesign the feed geometry of the magazine body, i.e., the feed lips?  
3. Can you elaborate on the problems you have seen with the tan follower mags?  You may have seen the recent threads from Battlefield Las Vegas, a public shooting range, in which they run significant amounts of ammo per month, and they reported the tan mags to be the most reliable they have used.  

Thanks!

The follower won't have anything to do with the feed angle, that's all the lips.  As far as having major problems with tan follower mags...  I'd look at something other than the mags.  I've seen literally hundreds of these in use since '09 and other than a small handfull of Centers that don't drop free, they all work perfectly.  I think they're a significant improvement over the green followers and old springs.  
We run them in 10.3" full auto suppressed Colts with all stock parts, with M855 and MK262.

Yes I saw the thread from Battlefield Las Vegas
I was actually pretty surprised with what they said about choosing the brown mag.
I have not checked to see where M855A1 hits the feed ramp with the green follower.

For magazine reliability in general  I am basing my findings solely off my military experience. Currently hitting 25yrs!

Since the issuing of the brown follower mag, in working with other units (mainly regular Army) over the past two years I have seen more double feeds with those mags than any other.
(This is based on training with company size units 100 plus soldiers at a time.)  
With double feeds being 90% mag related I do not think they are standing up as well as the old green follower mags.
I have green follower mags that are at least 10 years old and although I do not run them all the time they still work great.
Soldiers are probably the hardest on mags, Magazines get stored full for months at a time during deployments, shot a lot and thrown into piles mixed around. Dumped on steel vehicle floors. Some units treat them as accountable property, so the mags you get issued could have come from others that never took care of them and have been rotated around a company forever. Who knows how many rounds have been thru them.  

Let me hit M855A1 again..
This thread was great in that it has really explained why M855A1 is chewing up feed ramps (which is being reported) lets not even bring up over pressure prematurely blowing out gas ports in barrels
increase in broken bolts and other issues.
M855A1 although has been in use in Afghanistan since 2012, it has not been issued stateside until last year at most bases.
Now that it is the primary ammo across the board (for Army) I think over the next year or two once high round counts have been hit in training
that we will see exactly the effect the ammunition is having long term on rifles.
As is correct with this thread, it has already been determined we now need a special magazine just for this ammo on the military side.

My humble experience with magazines, As I shoot about 10-15,000rds of different 5.56 a year thru the military and the fact that I like shooting 3gun.

Lancers I have the original and the Advanced Warfighter from when they first came out multiple trips down range still run awesome
Magpul mags Run great I have had some wear out  (double feeding) and I despise the fact that they allow you to jam 31 in there if you are not careful (leading to not seating on a closed bolt)
But Magpul mags I have found reliable enough I trust them in combat. (Love the Emag wish I had more.)
ETS   Tested them for Defensereview.com they run great super smooth and I love how you can attach them together (long over do with U.S. mags)
One thing I should check and post on this thread is where IMI Defense mags let M855A1 hit the feed ramp.
I am currently running a lot IMI Defense G1 and G2 magazines. Totally pleased with them so far.
IMI Defense Magazines on DR
ETS Magazines on DR


Samuse you are correct I was meaning brown follower magazines in general, not that the brown follower being the issue of the M855A1 feed ramp problems.

Magazines I think can fall into experiences can vary. Obviously if a certain one works for you then why not swear by its use.

One aspect left out since this thread is on M855A1 is other military ammo. (And the slight variances in the length and shapes of the tips  (nose of the round) of civilian vs. military 5.56. (yes takes a micrometer to measure but its there.)
Take MK262 for example because of its flat nose (hollow for stability) there are some magazines that it just does not run well in. Due to feed lip design and height of the front wall of the magazine with
Mk262 in certain mags can sometimes catch on the front lip of the magazine as it feeds (loosing energy to properly chamber.)

So for me for any magazine to be deemed truly reliable should be tested with various types of military ammo.
Perhaps the diet of all civilian ammo at Battlefield Las Vegas has led to them having great success with the brown follower Magazine.  

Bottom line if it works well for you by all means stick with it!

Sir, this is a great post.  As a suggestion, you could do live fire feed tests by only loading the M855A1 round below a different live round.  The question really has more to do with how it feeds while undergoing recoil conditions, rather than how it fires.  Pressure and bolt cycle rate may not be identicle, but it'll be the best live-fire data you can get without actually firing it.

Since M855A1 has a very high pressure spec (something which does not fill me with great opinion on this ammunition, personally), my suggestion is to use the highest port pressure ammunition you can find.  Overcharged handloads even, if you are a reloader.

Wear your safety glasses!

Y'all should like...totally send me one of those!

Done! Sent via arfocm email thingamajig.

Really appreciate it.

Interesting thread OP.

I've shot ~ 2500 rounds in a local monthly match over the last few years.  I typically use Lancer L5 AWM or Magpul M2/M3s.

Anecdotally during this time, I've had 4 failure to loads - all with the Lancers.  Although one was a bullet issue - hit feed ramps and the round setback nearly all the way into the case.

I remember the FTLs only because mag related issues don't happen often and when the clock is running - hardware issues are irritating.   Software issues are more common