I just recently put a brand new outer barrel on my CA m15a2. When I put the thing back together and went to shoot it, the first trigger pull would result in nothing and the second trigger pull would send 2 bbs practically rolling out of the barrel. They would only go about 10 ft. On full auto, the same thing happens with it skipping some shots and then sending 2 together with no juice at all. HEELP!!!