Different alloy mixes will result in different bullet diameters.
The molds I have used cast true diameters when I sort out the
Clip
On
Wheel
Weights, and only use those.
The stick on weights are too soft, the zinc weights make the alloy melt at too high of a temp.
The steel weights? well, hopefully, you do not melt those!!
I sorted about 1/3 of a bucket of COWW's on Tuesday, That sorting took an hour.
The ingots that resulted seem to be perfect hardness,,
I cast about 50 bullets that day, I am waiting a week before I PC them,,
to see if the alloy gets harder with time, as I have read,,