There are a lot of things to consider. I know someone who tried this. Turned all of the gas on in the house, then used a shotgun in the mouth and ended up getting blown back through a window. He mangled his face, basically took his entire lower jaw and side of his face off, but otherwise he is fully functional but disfigured. I'm sure it depends on placement, whether you move when you pull the trigger, even slightly turning your head could end up with you just disfiguring yourself like the person I knew. I mean, he even used a secondary method of causing a fire, planning to burn in the house after he did it, but neither method got him. The good thing, though, is that he was no longer suicidal after that and has 5 kids now, married and is pretty happy overall.
