Thanks !!! That is an idea well worth trying. I cast for a .357 magnum rifle. My Lee 358-200-RF projectiles at 950 fps have been my most consistently accurate bullets (maybe 2 MOA) and they are cast from roofing lead with around 2% tin from solder. But my 158 and 125 grain projectiles aren't as accurate made from this alloy. Recently I got some very pleasing groups with the smaller bullets using a 50:50 mix of wheel weights and roofing lead. So thanks for the pencil-testing idea.... I now have a hardness indicating method that will help me in my experiments. Best wishes from New Zealand.