Welcome to the Forum. You may get an award for most dramatic 1st post and longest running thread from that post! I am glad you are not hurt.
As this is a forum you can see that everyone has an opinion. Some are more helpful than others. What none of us know is what really happened. Only you know the circumstances that occured and even you don't know the root cause the malfunction. You will/should get a new gun from S&W. Hopefully, you will get an explanation. I was also in the Army and have fired 1000's of rounds of 5.56 ammo from lots of different M16s and also AR 15s in civilian life. I have never seen this happen. It would scare me and make me angry if it happened to me as well. I hope you let us know the outcome from S&W and or Ammo manufacturer (Federal) if they give you a plausible explanation. If they don't, I hope you come back to the forum anyway, as this is a pretty good bunch of people to share info and experiences with. Again welcome.

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