I recently put together a new SBR upper, using a blemished BCM upper, 11.5 inch BCM BFH barrel, and one of the Rubber City Armory coated BCGs. Vltor low pro gas block and BCM charging handle are also installed. This is also set up for a suppressor, and I am using an OPS Inc M4M and M4S , but primarily the M4M.
So I take it out the other day for the first time to get it zeroed. Once irons and RDS were gtg, I attached the M4M and ran some rounds through, same with the M4S. Fired a total of about 140 rounds, pretty even between Fed. XM193 and Hornady steel training rounds (limited range time this day). Probably about 80 of them were suppressed. All functioned fine, one fail to lock back on a 20 rnd Pmag I was using on the bench while zeroing.
So here is my concern. When cleaning, I noted some wear/gouging at the rear part of the cam pin pocket on the upper. There is also a bit at the front of the pocket, but this looks like finish wear, no material removed (sorry, no pics). I also noted some slight wear in the finish on side of the cam pin "cap" (for lack of a better term). I searched and found varying opinions on how normal this is. Only one of my other rifles shows this type of wear, a fairly beat Colt carbine.
This is my first SBR, and my first time with suppressors. I was using a H2 buffer with a blue Sprinco recoil spring. I am not sure if this is a timing issue with the BCG, or was an indicator of another problem. The cam pin cap measured within a few thousandths of others I have in other rifles. Could overgassing be causing this wear, and would using a H3 buffer to slow the BCG help?
Thanks for any help you can provide.


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