Our group does like a bit of Bang!, but one of the problems we have with it is this: there's no reliable way to guess how long a game of it is going to take, which, combined with the fact that players can get knocked out very early on, means that sometimes it goes on and on long past the point where some people in the room or even still playing are fed up with it.
As such, can your gunfighter elect to do the decent thing and shoot themselves in the head to spare themselves the misery? More importantly, if you shoot yourself from behind a Barrel, do you get to draw to see if your barrel protects you from damage?
(It's been a while since I last asked a question here, so I'm glad to be getting back into the fray with an issue as complex and important as this one.)