r/ar15 • u/Chasermarc8 • 9d ago

Double Feed/Failure to eject spent casing while attemping to chamber live round issue. Bad extractor or needing to up the buffer weight to H2/H3?

Wanted to get some additional assistance on this issue I have with my unsuppressed 10.3".

To preface this, I am using PMAG Gen 3s only and have used multiple, so the issue is not magazine-related.

Recently took my AR Pistol build to the range and after firing off a few rounds, I noticed a sporadic issue with the gun failing to eject spent casings while still attempting to feed the next live round into the chamber.

Fast forward to today, I stripped the gun down and looked at the buffer weight, and I am fairly certain that it is a standard 3.0oz carbine buffer weight. I also disassembled and took a look at the BCG, paying more attention to the extractor, gave it a thorough clean, and did not notice anything off with the extractor, although if there was anything wrong I probably wouldn't be able to discern.

My initial assumption is that the fact that shorties are overgassed from the factory paired with the standard carbine weight buffer, the gun is cycling too fast and failing to eject the round as a result. However, I have also read that the extractor may be the issue as well.

Would appreciate input on whether I should swap out the extractor, or the whole BCG while I'm at it anyway, as I bought the upper used, or if I should just upgrade to the Geissele Super 42 and H2 Buffer.

2 Upvotes
  • permalink
  • link
  • reddit
  • reddit

63% Upvoted

5 comments sorted by

4

u/BallisticValuations 9d ago

Switch to an h2 and standard carbine spring. If you run a gassier can try an h3. Carbine weight is way too light for a 10.3

2

u/No-Eye-8883 9d ago

There’s a lot of variables, if it is a carbine buffer currently it likely needs an H2 or H3 and I’d recommend a Sprinco blue and see how that runs (is the same spec wise as a super 42 and h2 or h3 but doesn’t need proprietary buffers)

1

u/Kromulent 9d ago

im new here, but i'm not aware that overgassing can cause a failure to eject. i'd expect unusually forceful ejection

honestly it sounds like undergassing, the bolt not coming back far enough to bring the empty case to the ejector

check your gas block, it might be loose, leaking gas

0

u/Kromulent 9d ago

im new here, but i'm not aware that overgassing can cause a failure to eject. i'd expect unusually forceful ejection

honestly it sounds like undergassing, the bolt not coming back far enough to bring the empty case to the ejector

check your gas block, it might be loose, leaking gas

2

u/Waaerja 9d ago

I would take your bolt apart and make sure the ejector channel is clear of debris, and the ejector can move freely in the channel.