The solder is for the tin content. It's supposed to fill out the mold nicer. Most any 95/5 plumbing solder will do. I just ordered the Lyman 4 cavity molds for 9mm,.40, and .45. Can't wait to try them out. I have a single mould for a 124 gr 9mm hollow point as well.First cast BOOLITS hehehehehehehehehehehh
230 grain Truncated Cones
Lee 2 cavity aluminum mold
tumble lubed with lee ALOX
Someone told me the steel molds are easier to keep a constant temperature as the aluminum ones cool off too quickly.