Kaboom! The Story behind the Picture
From the AR15.com Discussion Forum:
"Would not believe it if I hadn't seen it! We were shooting our monthly offhand, winter fun shoot, when I heard the line officer yelling "cease fire, cease fire". One of the shooters had a MAJOR malfunction!! When I approached, I found an AR with NO upper receiver, none! The bolt was stuck in the barrel extension like a spark plug.
When the carrier started moving rearward, the bolt, for some reason rotated only a few degrees and LOCKED UP! The carrier continued to the rear and was split down the middle by the cam pin, as though you were splitting a log. As the carrier split, it blew the upper into two large pieces and a few smaller ones. The left half of the upper flew about 15' grazing a fellow on the bridge of the nose causing a very minor cut. The right half flew about ten feet. The left half of the carrier followed the left half of the upper while the right half of the carrier moved to the rear far enough to lodge in the buffer tube about an inch. The guts of the mag were blown out the bottom, and the magwell of the Eagle Arms lower was bulged about 3/16ths" on each side. The shooter sustained NO injuries. The shooter is a seasoned highpower veteran, and experienced reloader.
When the bolt was finally removed from the barrel extension, it was found that the rear of the cartridge case had been crumpled and looked like a belted magnum. The extractor had been blown loose, with its front section bent back into the barrel extension. This is what stopped the rotation of the bolt. When the extractor blew, it took a piece of the base of the case with it, undoubtedly venting massive amounts of gas into the upper. I personally don't feel this alone would be enough to destroy an upper upper. It could certainly cause severe damage. It was the splitting of the carrier that amazed me. Last night I was talking to 6 or 8 guys who were there. A few of us noticed the same thing. When the carrier split, it exposed the grain of the metal. The area in front of the cam pin had a different look. We knew when the thing let go that a lot of gas was present in that area, but we did not feel the gas alone was responsible for the difference. A few of us are of the opinion that there may have been a small fracture in the carrier in front of the cam pin. This was about the first thing I noticed at the range that day. It had an oxidized look, something I didn't feel could occur in one quick instant."
Click the following images to see more photos!
The description and photos on these pages are from the Winter of 1999 to 2000. I had hosted these photos when this had happened and I had always planned to get this page up as a lesson for anybody that should take the time to visit as subsequent investigations into the above KABOOM showed that the cause of this major malfunction was sloppy reloading practices! Some of the loaded rounds were disassembled after this event and it was discovered that pistol powder had been used to load some cartridges. The error seems to have come from emptying a powder measurer into a container that was labeled
incorrectly. In the process, when the shooter went to reload the next time he managed to use pistol powder instead of the rifle powder he thought he was using. The faster burn rate of this pistol powder caused dramatically increased pressures and the subsequent explosion of this AR15. I think the photos really tell a story that we would all be wise to listen to!