This is a 45 acp miha mold, I got it with penta HP and regular round HP.
Round HP on the left, penta on the right. Same in the next pic;
These were cast from some real soft nearly pure lead with enough tin to get good fill-out. Harder lead resulted in much less expansion. But @ 45 acp velocities, that's not hard to understand.
These were cast of wheel weights, they expand, but not like the above softer boolits.