I posted on this rifle a year ago I guess. I never did find which piece is out of spec. This rifle groups well. The issue is the bolt barley contacts the left side cartridge when cycling / being fired . Fact check. Several ruger 20 rnd mags used. All had stoppages. Several different brands of 5.56 used. Federal xm193 , Winchester, SA battle pack 5.56. It’s not the ammo. At least 2 stoppages a mag. The bolt is barely making contact with round trying to push it in chamber. I have a blued 580 series and the bolt contacts it twice as much vs the SS rifle. I have swapped various parts to try to figure out where the out of tolerance is at. I’m down to the mag latch height or receiver trigger guard shelf not in the right spot as far as height is concerned. I guess I need to send it back to ruger. How big of pain is it to send back. I don’t have a box. And will they ( ups ) come to the house and pick it up. Ty Wardawg