I have been casting roundballs and want to cast some .45 lswc. I have pure lead, Im loading for about 875fps, I figure I need about 20-1 tin, am I thinking right? How do you figure how to get the right proportion, wieghting them? I have sheet lead that I am in the process of making into about four pound igots. Any suggestions on where to pick up some tin? I have had good luck with the Lee mold for my muzzleloader, is it a good way to go for the .45? Thanks, Ken

Ken
It's my understanding that the tin does not do much in the way of hardening of the alloy, least not as much as antimony does. I use one spool of 50/50 tin/lead to a 20 pound pot of wheel weights to aid in casting.
Something you may wish to keep in mind is lead by itself and a lead/tin alloy will produce some of the smallist diameter bullets for a particular bullet mold. A .452 mold may produce bullets having a diameter of .451.
Jim

That is much too soft. I would contact the antimony man, Bill Ferguson, and get some antimony and tin to add to that lead. He sends an alloying sheet with an order. Wheel weights with a small amount of tin to make casting easier also is a good mix.
Personally, I save pure lead for muzzle loaders and mixed with tin, for BPCR's. I use free wheel weights for alloying everything else.

If you are on the east coast try G.A.R. out of N.J.. No web address but good resource for what he calls bullet enrichment materiel, a tin, antimony, lead mix. it works good with pure lead. I would try to trade pure lead for WW with a caster in your area and avoid any shipping. You may even get 6 lbs for 5 or even more if melted into ingots. Gianni.