the carrier group would come forward and get jammed up about 1/2" from being completely into battery. After extracting the round, every time the case would be seriously dented and scratched from the bolt lugs digging into it.
I recall an issue like yours in the AR15.com forums. Some respondents suggested trying H through H3 buffers, while others suggested H2 & 3 only... and others suggested that it was ammo issues.
Ultimately, the OP removed the Larue m16 BCG and swapped in a S&W M&P 15 BCG and it "worked flawlessly suppressed and unsuppressed".
There was a lot of conjecture as to what was different between the two BCGs, but the only stand-out variation (according to the OP) was that the S&W BCG was 2 ounces heavier than the Larue.