This is what happens when you have widespread gun control (not that this yahoo would not have died by something else just as stupid).
Parents who own weapons always teach their children from the time the kids can walk the two prime rules of weapons (listed here for lurkers — every FReeper knows this already):
1. Always assume it is loaded
2. Never point it at something you do not wish to destroy (that includes your head)
3. If you ever play Russian roulette with a semi-automatic weapon please have your friends go first.