I just received a new bolt carrier group for a new ar build. It does not have a name attached to it like DD or LMT or RCA. The description states HPT, MPI, Shot peened, Carpenter 158, 8620 steel, chrome lined carrier key and bolt, grade 8 screws and so on. I put it all together all torqued to proper spec, finished the trigger work and thoroughly cleaned the BCG as I normally would and headed for the hills. I only fired 40 rounds as I had received a few short strokes, which usually means gas leak. I checked the gas block alignment, and gas tube. Then I noticed some fouling around the front base and sides of the gas key. I thought I had the proper amount of lube inside the bolt, it was not dripping wet. I took a small air bulb that I use to clean lens, closed the bolt and blew air into the gas key, it started bubbling around the base and the front base of the gas key. All the screws are still staked and tight.
I admit, I've never been this ocd about a gas gun build. I also know that gas leaks cause premature failure. Many websites state that there are only a few companies that actually make bcg's and this bcg states that all testing and QC has been done.
After all that, are all bcg/gas keys going to leak a little? Short of buying the raw parts and hand lapping the key and the carrier and staking can I expect that a BCG from Daniel Defense or LMT to not have this happen to? Or am I too OCD?
I admit, I've never been this ocd about a gas gun build. I also know that gas leaks cause premature failure. Many websites state that there are only a few companies that actually make bcg's and this bcg states that all testing and QC has been done.
After all that, are all bcg/gas keys going to leak a little? Short of buying the raw parts and hand lapping the key and the carrier and staking can I expect that a BCG from Daniel Defense or LMT to not have this happen to? Or am I too OCD?
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