My son and I went to the range over the holiday weekend to shoot my new ar. Please keep in mind that i am fairly new to the world of black guns and it took some coaxing from my son to purchase my first ar it is an A3 configuration. The first ten to fifteen rounds went through it without any problems and then it started. The bolt wouldnt quite go all the way into battery once or maybe twice took it apart at the range didn't see anything obstructing the chamber or anything wrong with the bolt. So tried it again and click, nothing. Kicked that round out and cycled another one in and it looked like the bolt was closed and boom! The bottom of the magazine separated from the magazine the spring popped out along with the four remaining rounds and the bolt was stuck forward. Took the gun home got the bolt out and the extracter was bent the shell casing was ballooned at the base and there didn't appear to be any damage to the chamber or upper reciever. I've read about this happening to others and was wanting input as to what may have happened and what should be done to see that it doesn't happen again. The ammo was store bought and i've used it for years in my bolt guns without any problems. Oh yeah, this was not its maiden voyage it has had approximately 120 rounds through it. any input would be appreciated