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5/16/2014 7:36:41 AM EDT
What would cause the gas key and fasteners to snap clean off? I shot 3 rounds out of a pistol upper and none of the rounds cycled, so I disassembed the gun and found the gas key snapped clean off.
5/16/2014 7:56:00 AM EDT
[#1]
over-tightening with shitty parts most likely. What's the brand of the bolt carrier group?
5/16/2014 8:03:21 AM EDT
[#2]
A smaller, now defunct, company. Go figure.

But that's what I figured. I wasn't sure if it was really possible it had slapped the front of the upper on it's travel forward and that caused it to snap.
5/16/2014 8:10:48 AM EDT
[#3]
That's unfortunate. I would pick up a Bravo Company or Spike's Tactical bolt carrier group if it hasn't already been replaced.
5/16/2014 8:24:31 AM EDT
[#4]
Pick a supply for two new carrier key allen bolts.

Clean the mating sides of the bottom of key and the top of carrier.  

Put down a light coat of red loctite across both mating surfaces (being used as a gasket compound here), tighten the new bolts to 37 in lbs, then stake the key metal into the side spines of the bolt head to retain the bolts.  Lastly, just give the end of a key a good blow to clear any loctite that get into the gas passage channel.
Note, do not strike the bolt heads to flow any of its metal to the key.  The bolt is hardened, and will just end up with the bolts loose and snapped again.  So again, the key is peened to flow it's softer metal into the side spines of the bolts to retain the torqued 37 inlbs in place.
5/17/2014 7:40:47 AM EDT
[#5]
Quote History
Quoted:
Pick a supply for two new carrier key allen bolts.

Clean the mating sides of the bottom of key and the top of carrier.  

Put down a light coat of red loctite across both mating surfaces (being used as a gasket compound here), tighten the new bolts to 37 in lbs, then stake the key metal into the side spines of the bolt head to retain the bolts.  Lastly, just give the end of a key a good blow to clear any loctite that get into the gas passage channel.
Note, do not strike the bolt heads to flow any of its metal to the key.  The bolt is hardened, and will just end up with the bolts loose and snapped again.  So again, the key is peened to flow it's softer metal into the side spines of the bolts to retain the torqued 37 inlbs in place.
View Quote


This! The only thing I would add is take 10 minutes and lap the key to the carrier.
5/18/2014 5:21:01 AM EDT
[#6]
Send me an email if you still need a couple.  Too many places ding you for crazy shipping fees on small items.
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