Before I was casting my own I traded linotype to a guy for his cast boolits for my .454 Casull Encore barrel. They were an alloy of 2:1 lino:wheelweights - very hard. I had great accuracy and they would run big Iowa whitetails from stem to stern and keep going, no fracturing/brittleness there. Nowadays I cast softer boolits for my .357 Maximum and .30 caliber rifles and have great results as well.