I'm thinking of trying my hand at heat treating some of my cast bullets for experimentation purposes, and maybe for hunting if all goes well. I'm curious what lead alloy works best for heat treating. Best would be defined as: good hardness without becoming brittle, like linotype in the non-heat treated form. I'm looking for hard bullets 18-20BHN so I can avoid the gas checks if possible. I've read some on this matter, but am interested in what your experience has been.