I use 30-1 in my 45-70. 30 pounds lead I roll tin(95%) 5%antimony . With 20-1 use 20 pounds lead. In my muzzy I use pure lead though. I personally wouldn't go harder than 30-1 The hardness would be about 8 on the brinell scale. You can buy 30-1 lead ingots at midway, that's where I got mine.