[lloyd smale]

try finding a buckshot ball that fits as good as possible in the nose of your mold place mold in the pot until it starts to melt and then fill remaider of mold with harder alloy.

Ive heard of annealing brass like that but never cast bullets
Ive never seen a cast bullet change color

I have also read about attempts to create a "partition like" cast bullet but I forget where and how