Sorry it took so long to get back to you.

Just like almost all Kabooms, this was due to a round that had too much powder and had a case failure. Just glad it wasn't me. I have some pics of a nice "N" frame S&W that had the same problem, blew off the top strap though and cut the cylandier in half. I usally save them and post them when people start talking about Glocks Kabooming