Well buddy I can tell you this. The suppressor on my M1A works very well. No I did not do anything special to the gas system. But they are adjustable and if you over gas you can bend the op-rod. I have found both through research and my own trial & error that the M1A likes the 2550 fps range. I did some reading from the Springfield Armory where they suggested that and it works very well. I load 168 gr Nosler Competition with H-4895. I'm shooting 1/2" groups @ 100 sub moa. I also break my M1A down after each shooting session for a good cleaning. That also includes removing the gas system for a good cleaning. Sorry this is so long but I wanted to give you ALL the information. Hope it helps.