so I have had to take a break from shooting because of surgery. and with this much time just sitting around, I started wondering about the accuracy of my AR15. it has a 20" heavy barrel, and the accuracy has been ok, but not great. i am still trying to find a really good hand load for it. i have several times gotten just under moa, but nothing repeatable. i started thinking about the flash hider. the bottom port is close for obvious reasons. but I am thinking that the gas flow may not be even, kicking the bullets a bit as it leaves the barrel. has anyone tested for this? I understand that the military would be more concerned about keeping soldiers alive (breaking up muzzle flash) over loosing a bit of accuracy. it would take one cool cat to be able to shoot sub moa in a fire fight! I am thinking about getting a muzzle break and just a thread protector, because I know anything I do is going to change the barrel harmonics.