Adding any lead to the magnum shot will just dilute to antimony and arsenic. Suggest you Google Paco Kelly and research his articles on the 30-30. Magnum shot WQ’d was his favorite alloy for hunting. I suggest you add 3% tin to the magnum shot if you have a quantity for an excellent ternary alloy that then can be mixed at 50/50 with lead for an excellent alloy for hunting cast bullets also.