I was shooting yesterday and on the last round of the day I had the primer pop out of the case. The ammo in question is winchester Q3131 with an 07 headstamp(also has a NATO headstamp if it matters). The gun I was using when it happened was a 20" gov’t profile upper from Bushmaster. I had just oiled the gun about ten rounds or so before the popped primer and I probably over oil stuff so it may be possible too much oil got in the chamber. I also shot the same ammo out of a surplus M16A1 upper (which has a brand new mil. A1 pencil barrel) without issue. Is this a case of a bad round, a bad chamber, or me over oiling? I don’t know if this is a big deal, but I thought I better get to the bottom of this.
Shoot more and report back. One incident is not enough to analyze a trend.
Gotcha. It’s been my practice ammo so I’ll try to shoot some more at some point in the near future.
My friend was having the same issues with the same type of ammo. Primers were popping out of almost every single shell.
Yep - smells like a trend is happening. Might be a QC issues.
Check to make sure the chamber is 5.56 not .223. A .223 chamber could be the real issue, not the ammo.
Wincheter USA used to have 2 loads listed as Q 3131 and (Q3131 A or -1 I believe). The difference was 3131 was standard pressure and 3131 A was loaded to 5.56 NATO pressue. Some boxes I’ve seen were marked as 5.56 while the standard was 223.
I justed checked there online catalog and it only lists
Q3131 556 muzzle velocity 3270 55 gr
223R1 223 Rem muzzle velocity 3240 55 gr
223R3 223 Rem, muzzle velocity 3100 62 gr
If you are having primers pop out shooting Q3131 marked 5.56, check your chamber to insure it is a 5.56 chamber and not 223 Rem which Bushmaster is famous for. Another way is to shoot the bushmaster accross a chrono and see what it is giving you and compare against a likewise Colt A2. The Bushmaster is proably pushing 3350 or better.
Ned Christianson Had a simular observation which led to his chamber reamer and 5.56/223 chamber guages.
Both Q3131 and Q3131A are 5.56 loads. The difference is that Q3131A is made in Israel.
I was reading an article concerning thr Winchester USA Q 3131 and the point of the article was that if you were using the ‘A’ load to insure that you had a 5.56 chamber and not a regular 223 Rem because it was loaded to 5.56 presures.
Since going to Winchesters site this afternoon, I see that they have changed the number on the standard loading to help clarify it.
I wasn’t aware that the 3131A was loaded in Israel. You learn something new every day.
My information is that it’s fairly common for this ammo to pop primers.
Yep. Q3131 has had this reputation for years. Nothing new.
I have 2 guns that were dumping primers left and right with the 3131A, but my buddy’s gun ran with out issue. I was told to get the chambers reamed. If I can find a real 5.56 (hopefully Ned Christiansen’s) reamer in Cincinnati I’m gonna do that to be sure its not the guns. BUT, are you saying not to get to wraped around the axel if this stuff chucks primers every where and nothing else does?
That’s what I was thinking. The only thing that had me wondering was that it just happened to occur in a bushmaster I hadn’t shot much. I’ll just have to watch what I put through that gun and see if anything else happens at this point.
For you guys that have popped the primers, measure the primer pocket/hole in the brass.
I had this with some ADCOM ammo, 99 lot IIRC. The 98 stuff was fine. I’ve heard that it was “over pressure” but when I reloaded some of it and the primer fell out in the ammo hopper of the press.
That led me to think pressure had nothing to do with it. I found the primer hole was .177" Vs .175" for the brass that worked. It seems the sealer was holding the primer in.
Jeez! Q3131 is still TRASH!
If I can get some pics of this last two boxes I just got, I’ll start a new thread. Mixed headstamps (3 different years), a damaged bullet, and a badly damaged case mouth on one of the rounds… probably unsafe to fire.
I too blew a primer in a lot of 3131A in a 20" Bushy several years ago. Also had several pierced primers out of that case. That stuff was hot, OR had thin primer cups. I’ve never had an issue with Federal XM193 or AE, though.
In this case: Most likely the ammo, and not the gun.
While there are exceptions, Bushmaster chambers will tend to be ~5.56mm. Unlike certain others which hardly ever are, despite markings.
I picked up some 2 months ago headstamped 08and 07 mostly 08 it was fine better looking than xm193 I still have a few boxes unopened if i remember right it is q3131a. Is this something that has just recently started to show up?
The brass looks shiney on my 3131, but that doesn’t mean shit for performance.
I bought Q3131 two years ago that was similar to this poo poo. A couple of boxes from Sports Authority just because I was in the store. 
Anyway, it’s the same nasty stuff. It was mixed head stamps back then, and I can remember getting one malf out of the two boxes I shot.
With the new stuff I just got, there were the two damaged rounds, mixed headstamps (which I wouldn’t care if the ammo was good), and the case mouths/crimps look like hell!
There’s a factory crimp on them, and the case mouths aren’t uniform in length. I don’t mean from round to round, but on the individual rounds the brass is longer on some sides of the cartridge. The look really sloppy and rough. In addition, the case necks aren’t sealed.
Any one of these things wouldn’t be the end of the world if it were the only issue in a box of ammo. But all of this slop in such a small sample is nasty. I’m going to shoot it tonight… if I get any malfs, it’ll be the icing on the crap cake.
Interestingly, my boxes of Winchester ammo are marked Q3131A1. The boxes are all marked 5.56mm, FMJ, blah blah blah, but on the back it says Made in R.O. Korea. Never noticed that until now.
Q3131 is supposed to emulate M193, correct?
-B