I've got a Colt AR that I used to use for 3-gun. I had an el-cheapo, and stupid-loud brake on it and it shot great. But then then accuracy started going downhill. I took a look at El-Cheapo, and found that it was starting to wear, where the bullet passed was out of round. So, I decided to go quality- I bought a VG6 epsilon, and accuracy has not improved. I've tried commercial ammo, handloads (that shoot great in other ARs) and can't get better than ~3MOA when it used to shoot closer to 1. Looking at the design, I see that the hole near the threads is close to round (.223) size, then it goes into an expansion chamber- and then it necks down again to near .223 size. Doing some reading, and comparing it to other brakes, that's unusual. Usually the second bore is quite a bit larger- closer to what flash hiders do. Or not- a lot of these have a small exit hole Can a muzzle brake have that big a difference in accuracy? I know it can change POI because of harmonics, but this is simply worse accuracy. I'm going to test it with a simple YHM flash hider to see if accuracy improves. The other possibility is that I've shot out the barrel, but it has <2000 rounds through it so that seems low for it to shoot that poorly.