FTF Failure to Feed

Round stubs on the face of the chamber and wont feed. This happens about every five rounds or sooner. I dd manage to get a get a 30 round mag to fire but this was the exception to the rule. Is it safe to chamfer the feed ramp (bottom edge of chamber) to help with feeding?

i have this exact same problem with hollowpoints. my rifle works perfectly with FJM or JSP, and it will even fire HP's perfectly from my drum, but if i load them into 30rd mags the jam into the edge of the chamber and stoppage occours. and you nailed my question as well. anybody know what to do about it?

Filing a chamfer should be a last resort, primarily because if you take off to much the case could end up unsupported.
First, try other magazines.
If that doesn't solve the problem, make sure the magazines are locked up tight. Is there any vertical movement when the magazine is locked in? If so, hold the magazine with the support hand and push it up while firing.
does the rifle now cycle?

How many cartridges have you fired through the rifle?

Poly is right. I had the same problem with my 5.45 rifle. The rounds would impact on the chamber face. If I pull back on the mags as I shoot, it works perfectly. I need to have the selector stop removed and ground down to fix the problem.

Thanks for the input.

I looked at the rifle after reading your post, and after chamfering the chamber face. I unlocked the mag and tilted it as far as I could without over riding the round in the mag and it would still hit the chamber face. What I did was take a dremel (OMG) and polished (not ground) a slight chamfer under the chamber so as to just change the angle of the face from perpendicular to slightly beveled with a nice polish. It's hard to describe but I didn't go into the chamber at all. I basically took the slight chamfer already there and extended it down the face at the breach and V shaped. Now the round comes out of the mag hits this slight chamfer and I can chamber a round with my finger where as before it would barely chamber with the bolt slamming forward. The cartridge is still supported as before but now there's a ramp (slight ramp) that sends it upward toward the chamber. If I can figure out how to post pictures I will post a couple.

I'm also working on mag woble and I'll let you know what I did with that as well. No this didn't cause the feeding problems as I held the mag to both sides and front and rear while firing a couple mags and it still jammed.

I'll be shooting it this weekend or next and I'll let you know how it works.

For anyone interested in how this turned out.

I fired the gun last weekend and it worked flawlessly.

The mag wobble is non existent and it fed every round without a single stoppage.

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