To the contrary Blammer, the harder the lead, the more likely it is to shatter or break, depending primarly on the hardening eliment! Lead(galina) in it's natural state is a chrystaline.
Smelting will reduce it to a soft solid, however, if you add another chrystiline as a hardner, such as antimony,in quanitys in excess of 6--8% the lead will once again become chrystaline!
On the average, wheel wieght lead is 95% lead, 2% tin and 3% antimony.
I use nothing harder then WW lead. Some times I will add a bit more tin, to make it flow better, and make it a smidgen harder, and if I want the bullet a bit harder, without altering the alloy, I will water quench.
I've had #2 bullet lead, which is 92% lead, 2% tin 6% antimony,
shot at velocitys over 2000fps, actually explode!
