As usual, that depends. IF you exclude successful and attempted suicides, the ten year period between 1991 and 2000 averaged just under 1,100 fatal or non-fatal self shootings a year. A high percentage of those were hunting accidents; and a majority of those involved tree stands and those long recognized accidents waiting to happen, exposed hammer shotguns.
A much smaller percentage involved people who could and did put their finger on the trigger of a holstered pistol. A hazard I have condemned several times.
And the bulk of the remaining self-shootings can be summed up in one word. Stupidity. Or two words, arrant stupidity. Either way, it is stupid to point a gun you know or should know is loaded at yourself.