All the cast bullets I make are for handguns, and all are wheel weights only. The ones I have tested range from 11-13 BHN. There is no set formula for WW that I am aware of. Different countries have different standards I think. European WW (Volkswagon, BMW, Benz) seem a little softer, Asian (Toyota, KIA) are a little harder and American range all over the place. Pure lead only in a MZ. They have to be able to obitrate (swell up from firing pressure) to fit the bore.