The New York Times, of all places, has a rather awesome torture test of M4 rifles complete with kablooeys and fire.
One has to wonder why anyone would volunteer to fire a rifle in that way until it fails catastrophically. Kabooms are no laughing matter, and the results often lead to blood loss.
Still, the gun did a pretty excellent job, all things considered. I've never encountered weapon related issues with the M16 or AR15 rifles. Most jammages I've had were either user error, magazine related, or issues with ammunition: like that time at Paris Island where my next to last shot at the 500 yard line on qual day ended up going POP instead of BANG, with my bullet noticeably hitting the berm about eight feet down from the bull, which cost me the coveted Battalion High Shooter award. I did get the Company High Shooter award though.
Found at SaysUncle.