I have a new AR 15, 223. I put a mag of 5 rounds in and let the bolt go and it only went about 4/5 closed (say just before it cams to the chamber). I tried to pull back with the charging handle but it will not move forward or backwards. This is the first round to be put in the weapon. the forward assist doesn't help. This is a live round! This round is a reload, I was shooting another new AR using these same loads. I wouldn't have thought it would not have worked in this weapon. Any suggestions on how to get this they going???