Thanks folks, the help is appreciated. I'm not new to casting, though I started late in life, it was over 30 years ago. Round ball, well that's different, if you remember the scene from The Patriot where Mel is melting soldiers in a ladle and casting in a bag mold, that's my round ball experience. A Rapine mold and a stick handle ladle. Neither Mel nor myself had pretty balls! I do know that as little as 1% tin in the mix helps with unmentionable bullets, increasing Brinnel hardness by .3 and was wondering if anyone here had already experimented with adding tin for round ball.
Your time and wisdom is appreciated, truly!