RE: Lee r.e.a.l. bullets
i put my lead into a metal cup and set it on an coleman stove and turn it all the way up while the mold heats slowly on the other burner. Casted some of the prettiest balls last week.
Get your lead HOT and make sure you are skimming off the crap that floats to the top.
A little chunk of candle wax also helps clean the lead.