AR-15 failing to feed and gouging bullets, help!

[rpol98]

I also have a seekins dmr that's chambered in 6arc. Mine jams the same exact way and leaves the 2 gouges on the bullet. Berger 95gr classic hunters and 103 elder jam the same way. I'm using duramags. Have you found a solution?

you don't know if the 2 gouges on the bullet are from the mag feed lips, or from the M4 feed ramps of the barrel extension.

Metal mag feed lips usually carve out gouges on the brass, not so much the bullet projectile.

you probably have some serious sharp edges on the barrel extension feed ramps, left over from the usual machining. This is common with most AR barrels. Those sharp edges can be deburred and polished so you don't get gouges on the projectile, but that usually has to be done before the barrel is assembled to the upper.

The Other Site: how to romance your AR build

I'd guess that after 500 to 1,000 rounds of shooting, those sharp edges may just get "deburred" from normal usage. plus-or-minus. copper & brass wearing on steel.

 

[blee01]

It's doing it on both sides on the mag. Tried some 95gr vld hunters today and same thing. Seems like the feed ramps are not wide enough.

 

[rpol98]

It's doing it on both sides on the mag. Tried some 95gr vld hunters today and same thing. Seems like the feed ramps are not wide enough.

without seeing your barrel extension or your feed ramps, I'd guess it's not the width of the feed ramp itself, but the corners shown below in the red circles.

 

[Turpentine21]

It's doing it on both sides on the mag. Tried some 95gr vld hunters today and same thing. Seems like the feed ramps are not wide enough

If your bullets look like the bullets in the photos posted by the op I'm inclined to say it's a feedramp issue. Unless the mag feed lips are really tight and releasing the rear of the cartridge late. This lets the bolt jam the bullet into the feed ramps and doesn't allow the case to pop up out of the mag quick enough.

 

[ARlife4me]

I sent it back to seekins, they cut back the barrel and rechambered with a new reamer then polished the feed ramps. Everything is seeming to work well now from what I can tell.

so, it's running 100% now?

 

[dfanonymous]

NH₄NO₃ AL, is the best ammirite?

 

[ARlife4me]

NH₄NO₃ AL, is the best ammirite?

maybe i need to use that instead of 46-0-0

 

[dfanonymous]

maybe i need to use that instead of 46-0-0

I'm sure the OP knows one way or another