Class is in session! Several have recently asked some questions regarding the basics of casting for Black Powder. So without any further ado, let's get going!
Where to start? Well, let's start with casting pots.
Casting Pots and Furnaces
Folks have been casting lead projectiles for their black powder firearms almost since the advent of the black powder firearm. Early endeavors probably found shooters using nails, stones and small rocks in a blunderbuss type of firearm, but pretty soon they realized the ineffectivity of such endeavors ans searched for a better alternative, and lead fit the bill well. It was available, soft, malleable, heavy, carried downrange (kinetic) energy well, and packed a mean punch on impact. For centuries lead was traditionally cast over campfire coals and poured into handheld moulds. If you've ever watched Mel Gibson in "The Patriot" (as Benjamin Martin) melting down his slain son's lead soldiers over a campfire and pouring the lead into moulds, that was pretty close to what it was about. No fancy or expensive equipment is needed to get started; a simple cast iron melting pot, bullet mould, heat source and ladle are really the basic equipment one would need. It would probably be cheapest to start out with a simple Coleman stove and a cast iron lead pot. However, if casting over an open flame, you will have to keep a close eye on the lead temperature. A simple lead thermometer will help in this regard. If the lead is too hot, the projectiles will appear frosted looking and rough and won't want to drop out of the mould. Too cold and they will come out wrinkled and ugly looking. While many of the the electric pots are more expensive, they are thermostatically controlled and you never have to add stove fuel or propane, which can interrupt a really good casting session. Lee Precision makes several different models going from darn cheap (the Lee Melter), up to to the Production Pot models, available to hold up to 20# of lead and are still quite reasonable at around $80.00 (current pricing) and are available in bottom pour (spout) or ladle-type. One thing to bear in mind is a small pot like the Lee Melter (capacity 4#) will empty rather quickly. Then you have to add more lead and wait for it to come up to temp again. In the mean time your moulds have gone cold and you have to wait for THEM to heat up again. Wasted time. I would avoid the high priced RCBS or Lyman production furnaces for the moment. They are hundreds of dollars and PID controlled, (which is another story for later) and really overkill for the basic newcomer to casting.
Many times, lead comes in awkward or oversized pieces, and of questionable quality. Your lead pot (whichever type you favor) will like nice, clean lead to cast with. Most casters prefer to do their initial melting and fluxing separate from the bullet/ball casting sessions, and therefore melt the bulk lead, skim the dross off and flux it, then pour the purified lead into one pound ingot moulds. These are conveniently sized to fit most casting pots, and you can add an ingot once your pot gets down to about half full without having to worry about dross skimming or fluxing, and it will quickly melt and get up to casting temperature, as opposed to to dropping an ingot into an empty pot.
Lead Alloys
Before we go much further, I should mention there are may types of casting lead for firearms, including modern high velocity smokeless ammunition, which utilize all types of alloys, mixing pure lead with other metals such as tin, antimony, linotype and others. We won't discuss them in this tutorial, as for the new BP shooter casting round balls or conicals, we want as close to pure lead as possible. We get that by buying 99% pure lead ingots from shooting supply vendors such as MidwayUSA and others, or by metal vendors such as Rotometals. If you are getting scrap metal such as plumbers lead, roofing lead sheets, or scrap, you will need to flux and skim the alloys, impurities, dirt, etc from the lead before you attempt to cast with it...sometimes several times!
A couple caveats here I need to warn you about if you plan on using scrap lead; first, old wheel weights used to be a very popular way of getting free lead...tire shops would usually gladly dump 5 gallon pails of scrap wheel weights on anyone that asked. However, recent EPA restrictions have generally changed the makeup of wheel weights to those that no longer contain ANY lead. Plus, the new style of wheel weights are 'stick-on' rather than clip-on, and you can only imagine what sticky tape will do to your melting pot and casting equipment...
Second, as to the idea of using battery lead...there is one simple rule; DONT! The risk of injury to yourself or your casting environment is way too high from residual sulfuric acid, not to mention lead is porous and the sulfuric acid will permeate every pore of the lead, even if thoroughly rinsed. Once you start to melt it, you now release it into your casting equipment. So, don't go there. Don't even think about it. A long time ago a caster gave me some round balls he had cast from aircraft lead-acid battery vent plugs. They shot fine...but a week later I noticed my gun started sprouting a nasty yellowish-red corrosion in the bore and cylinder bores! It took multiple cleaning and oiling sessions to finally alleviate that problem, and bear in mind that cast iron or steel barrels have pores in the metal, too. Don't go there.
Moulds (or do you say "molds") are another matter of choice. Lee moulds are aluminum. This means they get up to temp quickly, but cool off just as quickly if you stop runnin' ball for any reason (like to fill the lead pot!). The RCBS or Lyman moulds are steel and once up to temp, stay hot a lot longer. Lee moulds are cheapest and come with handles. RCBS or Lyman...handles are extra (and pricey).
I'm gonna go out on a limb and recommend you start out with a 2 cavity mould to begin with, especially if you are ladle dipping but that's of course your preference. With a 2 cavity mould you can expect to cast several hundred RB an hour easy, way more if using a spout pot and 6 cavity mould. Just realize that if your temp is off you will be casting six duds instead of two that need to go back in the pot!
Two ways to view this; either go in as cheap and economic as possible to see how you like it, or jump into the deep end and get really decent equipment so you are not paying twice to upgrade later.
