"You can't use pure lead in handguns and modern rifles"
True, but you can use the pure lead to make a great alloy.
And there are many, many others. the tin and antimony are available at rotometals.
I load, 9mm Luger, 38 and 40 S&W, 38 Special, 357, 45ACP, 45 Colt, 223, 243 and 30-06