I used an alloy approximately 1 3/4 % tin, 2 1/2% antimony on mine, powder coated and water dropped after coming out of the oven from the pc since I had plans of seeing how fast I could run them. From the damage I saw there was definitely some mushrooming going on. I’ve read that the heat treated bullets act just like air dropped on impact , but hold the rifleing like harder alloys. I don’t have any way to show + or - on that, but they worked well so far on two does
