Tungsten alloys, carbide steel and beryllium coper have all been used in small bore military AP ammo, brass and iron were used by KTW, and of course everyone has heard of the DU penetrators used by tank guns.  And you're too late, lead ammunition has already been outlawed in some casesspecifically, waterfowl hunting, which is a Federal law, and California is trying to ban all lead bullets on the off chance one might be eaten by a condor.