I just finished my first build. When I installed the bolt carrier it was hanging up a little. It looks like the gas piston was rubbing just a little on the front site block. (I lined up the barrel as straight as I could when I installed it, went together good.) After cycling it a few times it seems to be loosing up. The problem that I have is that it wont strip the clip of a round and chamber it. When the bolt closes and strips the round from the mag, it drives it straight into the end of the barrel and not into the chamber. If I pull the charging handle all the way back and let it "slam" closed it will work maybe 3 out of five tries. I took another rifle that I have and compared the two. On my others it seems that the mag sits a little higher in the receiver than the one "I" just built. Is there a fix for this? does it just need a break in? I was using Wolf hollow points. I have heard of some rifles having problems feeding hallow points.