Was shooting AR yesterday. About 10 or 11th shot the rifle blew up. I was shooting factory rounds from a reputable manufacturer (bulk box of 1000). At the shot I felt powder hit my face. The bottom was blown out of the magazine and several rounds in the mag were dented/deformed. Bottom of bolt carrier was mangled. Got home and got the bolt back and this is what is left of the case and the projectile that came out has me dumbfounded. Take a look at pics and tell me your thought please.