Lyman lists linotype as having a BHN of 22, and wheel weights (not hardened) as having a BHN of 9. And that's for good wheel weights. I have run into softer ones.
Lyman #2 is listed with a BHN of 15. That is the exact same BHN they give for 50:50 linotype with pure lead. So, mix in an equal weight of pure lead with your linotype to arrive at the same hardness as #2 alloy. What you will end up with is about 2% tin and 6% antimony. This mix is also known as Teracorp magnum bullet alloy. It is not as pretty looking as #2 because it has less tin in it, but works pretty well.
Another approach would be to put 6½ pounds of linotype, 8 pounds of lead, and 8 ounces of lead-free plumbing solder (which is mostly tin) together. That will be very close to actual Lyman #2 alloy. Do be careful to double-check the MSDS of the lead-free plumbing solder online to make sure the brand you buy includes no zinc, but I don't believe much of it does. Zinc spoils mold fillout.
Might want to ask a moderator to move this thread to the cast bullet forum? You'll maybe get still more answers there?
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