360 partially rounded head bolt help

A lot of good answers. I just had a couple things to add. Since you have no welding equipment, you could use a $20 propane torch and it will help sometimes. Worse case scenario, get a $30 Dremel from Walmart and some cutoff wheels for it and grind the head off.Our local pawnshops have sockets by the pound and it is a cheap way to get a one time throwaway socket. I'd grab a cheap extension too and beat the hell out of it instead of the socket to drive one on. Or borrow a neighbors.