Common Causes of Stove Pipes in ARs?

[Jason Freeland]

I was testing 77 grain OTM ammo today out of my home built 1:7 twist 16 inch AR15 and was getting a lot of stove pipes, but only after it warmed up. The first mag was flawless, what are some of the common reasons that a AR15 might stove pipe when ejecting and it was also light primer striking the next shot often. Not sure how the two relate, but there it is. The gun fires 55 grain target ammo perfectly. Oh and both were Magpul Pmags gen 2, fresh out of the package. I wanted some commonality in my testing methods and that allowed me to try everything identical other than heat. The gun was freshly cleaned too.

First group AAC 77 grain Hornady projectile.

Second was AAC 77 grain with a Sierra Matchking OTM projectile.

Third was same as the first, but a different mag. Looks like the barrel likes heat, but not the action.

 

[Fredkrueger100]

Man that is odd. So you’re telling me the bullet is actually getting stuck in the barrel?? That is of major concern. Someone with more knowledge will have to chime in on this to help. I can only imagine either the primer didn’t ignite properly to cause the round to make it out of the barrel or there could be too much carbon buildup causing the stovepipe. But that would more than likely cause every round to do it. But I’m no expert.

 

[Jason Freeland]

Man that is odd. So you’re telling me the bullet is actually getting stuck in the barrel?? That is of major concern. Someone with more knowledge will have to chime in on this to help. I can only imagine either the primer didn’t ignite properly to cause the round to make it out of the barrel or there could be too much carbon buildup causing the stovepipe. But that would more than likely cause every round to do it. But I’m no expert.

Stovepiping is when the round doesn't fully eject before the next round is trying to load.

What you are thinking of is a squib load, that the bullet gets stuck in the barrel. I got in an H2 buffer today, so I will try to get to the range this weekend and try it out.

 

[RangerRick]

just a guess but how lubed up is the bolt carrier? sounds like it might be short stroke on carrier

 

[Jason Freeland]

just a guess but how lubed up is the bolt carrier? sounds like it might be short stroke on carrier

Pretty well lubed, I use CLP for cleaning. Works fine on 55 grain, it's just after she warms up on the 77 grain stuff that the problem showed up. I'm trying the new buffer and some different ammo (IMI Razorcore) this weekend, so we shall see what difference it makes.

 

[Jason Freeland]

Ok, first the buffer change worked fine, but I was still getting random light strikes and that got worse. I had the gun looked at and shot, by a professional, and he diagnosed a bad trigger. It was intermittently not opening all the way and also gave me some surprise bump fires. I had him change it out to make sure it was done properly. I plan on going back to the range tomorrow to try everything out again and make sure the new trigger works well. That being said, I love the IMI Razorcore I tried out.

25 rounds at 25 yards, would have been 30 but I got 5 light strikes.

 

[mr ed]

Light strikes can come from different things.
Put in a hammer spring of good quality.
Make sure it's in correctly and not reversed or you'll get johnny lawmaster syndrome.
Too light of buffer spring could not be holding the bolt closed.
If you slobber on lots of lube and it still does stove pipes, it's under gassed or extractor dropping round to soon. Does have the little rubber thingamajig under the extractor?
Open gas hole in barrel or play with different buffers.
There a ton of different things that caused your problems.
This is just a start.

 

[Jason Freeland]

Looks like the bulk of the problems have been solved, I only had one stovepipe today and no light strikes. Still would like to get to no stovepipes, but that will have to wait for another day. 30 rounds at 25 yards of IMI 77 grain Razorcore.

One "flyer" in the 7 ring , but otherwise nice n tight.