Formula for 6% antimony, assuming your clip-on wheelweight contains 3% antimony:
1 part Superhard
8 parts clip-on wheelweight
I also want to try boosting the arsenic and to that end I'll add reclaimed shot to the 6% alloy. Assuming that the 6% alloy contains 0.17% arsenic (NRA Cast Bullet manual page 127) and that the reclaimed shot contains 1% arsenic (typical but it varies tremendously) then the following mix would boost the arsenic to 0.3%, which I'm told is near optimal (NRA Cast Bullet manual page 126):
Formula to boost arsenic from 0.17% to 0.3%:
1 part reclaimed shot containing 1% arsenic
7 parts wheelweight or Super-Wheelweight
or Formula for 6% antimony and ~0.3% arsenic:
1 part Superhard
1 part reclaimed shot
7 parts clip-on wheelweight
Since we don't know the exact chemical composition of either wheelweight or relclaimed shot, these proposed formulas are not super precise but should get us in the ball park.
