I went to the range with my son-in-law to sight-in and put some rounds through an Adams piston AR that he picked up for a good price at Buds. (BTW it doesn't come with a chrome-lined barrel) It came without sights so I put my Aimpoint PRO on it for the outing. All in all, I was fairly impressed. We ran 200 rounds through it with no function issues (PMC ammo) and accuracy was okay with the PMC fodder. Other than the ejector dinging the brass quite strongly, everything else operated and looked normal. The big difference was how clean the BCG remained compared to my Colt! Although that's expected for piston guns, I was still impressed. We'll hit it again this weekend, maybe try some handloads to check accuracy.