What exactly is being overgassed! Bolt cycling to fast or just popping primers/extractor/ejector marks? If the buffer, spring and gas block are working as supposed to be then is it all about gas port size? Going off of 3 AR10's (6.5creed in faxon and criterion and 1 in 243win bear creek) that all are rifle length gas (12.7") and all the require something different for recoil systems. While I haven't checked port size against 2 Aero Precision 6.5creed barrel (that work well with standard weight carbine buffer, spring and a non-agb) that port size matters a ton! Why do these companies turn out barrels that don't work with standard weight recoil parts! Those 3 mentioned blow primers badly and have ruined many firing pins (steel and titanium). All 3 won't tune even with an agb and they do have the correct gas tube length. When I get time I'll pull the gb off and check port size against what works. The cbi barrel is a very accurate barrel, but stopped due to primers blowing. The same ammo in the AP barrels don't pop, so there's no issue with the hornady match 123sst/a-max ammo. Does anyone know what their port size is per barrels from the same or different companies? AP list their port size per system lengths and cartridges. I haven't checked throat differences per chamber either. Maybe just enough difference to cause issues?
