One of Greg Tanner's moulds could be easily be converted to a bag-type mold by trimming the Lyman handles and covering with leather or some other substance. As-is, with standard wood-covered handles, they're perfect for me. They will cast more good balls than will the bag moulds, but a separate cutter must be carried.
: Generally, the first couple balls will have to be re-melted, until the mould achieves the correct temperature. Normally, frosted balls only come from using an alloy with anitmony in it, with too hot a temp as well. Pure Plumbers lead will not cast a frosted ball, no matter what the temp. IF really pure lead is too hot, it will oxidize and turn blue on the surface very quickly, but without anitmony, it won't frost - at least mine doesn't. It needs anitmony to frost. Lead with animony in it can be softened slightly, by repeated melting and skimming without fluxing. The reason is that when the temp is coming up, the antimony willbe the last to melt, and lumps on the surface as a sludge. If this is skimmed off repeatedly, the alloy may be softened enough to shoot. It may take 10 cycles of melting, skimming, cooling down, melting, skimming cooling down, to work.
: Fluxing is ackomplished by the additon of beeswax, parrifin wax, bullet lube or Marvlux(what I use). The idea is to clean the lead of impurities and to combine it's elements into a homogeonus state. The reason to for perfect casts. The small plug (size of a pea) of 'stuff' is allowed to melt on top of the liquid lead(called 'the melt') then is stirred into the lead. The impurities (dirt) will rise to the surface to be skimmed off. Igniting(if wax is used) the flux will help reduce the smoke somewhat - just keep stirring until after the flame goes out. I woudn't do this on you wife's kitchen range.
: CAUTION!- make certain any lead you add to the pot is DRY- any moisture added to molten lead will cause an explsion on the surface and the molten lead to explode from the pot, covering everything around it including you. As the lead will be from 750 to 800 degrees,(normally) it will burn deeply as it sticks and keeps burning. Also, a BUG flying into melted lead will cause the same type of explosion. This has happened with a moth, in a garage and the resulting explosion of molten lead seriously burned the caster.
: Gloves and eye protection is also recommended, along with trousers and a long sleeved shirt.
