So I shot my New Frontier Armory AR45 today (Glock mags). The accuracy seems to be good, certainly what I would expect from an 8" barrel braced pistol. But the ammo feed and ejection, while mostly reliable, had a few FTFs. However, what I found most troubling was these very consistent dents in the brass. Suggestions? I am using a 10 ounce buffer and a stiff buffer spring designed for a PCC AR. The primers also look a bit flat to me.