If it shoots to the same POI as soft lead, I'd use it. I use cast bismuth round ball for hunting here. I use a .480 mold & a thicker patch. Casts at about 140 grains vs 160 for lead. Same POI out to 50 yards & beyond. Bismuth is hard -- very hard. It will shatter before it will deform. On water jugs, neither lead nor bismuth expanded even a little. The lead just had a slightly flattened face on one side. I figure as long as I'm shooting .45 or bigger, it's pre-expanded. I guess if you're worried about it, save it for the bigger bores.