My Bushmasters have chewed through thousands of rounds, and the only time I blew primers into the action involved a batch of my own "hot loads."
It always amazes me what BS sometimes circulates as knowledge. I'll put the purplest of all my Bushmasters up against anyone's Armalite, RRA, ASA, Oly, or Colt any day.
When I used to shoot two boxes of ammo an afternoon at the range I never experienced a great difference in my AR's. Then when I began to shoot two to three hundred rounds at a pop, the differences began to stand out.
The 'frankenguns' that once seemed reliable suddenly began to show their true weaknesses. Cases were stuck in their hot "match" chambers. Extractors failed to extract. Trigger and hammer pin holes elongated causing unsafe secondary to primary sear engagement etc.
However, the Bushmasters kept on ticking. Never once have I had to ram a stuck shell out of the chamber of a Bushmaster with a cleaning rod! I can't say that of my other AR's.
So, to those wise-a$$e$ who claim that Bushmasters are sub-standard I'll just say "prove it!"