by Rich Stern
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The economics of bullet casting Casting bullets is part of a hobby. Let's throw out the idea of valuing our time! This is fun and we can fine tune cast bullets to specific guns for better shooting. What more justification is needed?
Safety, safety, safety Our society has demonized lead in the last thirty years. The goverment would have you believe you'll fall over dead at the very sight of lead. It's not as bad as that, but common sense is required. Wash your hands frequently, and always before you are about to eat or drink after handling lead. Avoid touching your eyes, nose and mouth while handling this stuff. If your clothes get contaminated during the casting process, change them before resuming your normal family and work routines. No reason to put other people in jeopardy for lead exposure just because it's part of your hobby.
Minimal safety gear:
Optional, but a good idea for some folks:
Sources of lead Wheel weights are ideal for casting basic bullets. They contain a small amount of tin (about 0.5%), as well as antimony (about 5%). The tin makes the molten alloy flow better, and the antimony makes the alloy harder. Bullets made of wheel weights typically come out just right for moderate handgun velocities, and work well at modest rifle velocities if you add a gas check to the bullet. Casting experts have developed expertise in varying the alloys for different purposes. Specific amounts of tin and antimony can be added to create very different working properties for cast bullets, for specific uses. We'll leave the advanced metalurgy for the real experts. There are many resources on the Internet for such wisdom, and I've included a few references at the end of this article.
What you need to begin casting You can buy equipment specific to bullet casting. Or you can go the economy route, as I did. The cookware section at the local Walmart provided most of my gear. Here's my list and what each item cost. As you can see, there isn't much investment to get started.
Getting started It is critical that you have good working space. Outside and covered is ideal. We need to avoid the fumes, and we also need to avoid having any water near our melting pot. You must make sure that no moisture comes in contact with the molten alloy. A drop of water in the molten lead can cause a steam explosion, splattering molten lead all over you and anything else nearby. Water and molten metal do not mix! Some people advocate washing the wheel weights before melting them down. Not necessary, in my opinion. All the crud is going to come off in the metal soup when we flux it, so leave it dirty. If you do wash the wheel weights, let them dry for several days. It all has to be dry when it goes in the pot. For basic casting, use only the wheel weights that have the steel clips. The stick-on, adhesive backed wheel weights are pure lead; too soft for modern bullets. Save them for another day if you shoot black powder and want to cast your own muzzle loader balls, or you want to custom mix alloys by adding other casting metals. Put about 5 or 6 pounds of wheel weights in the pot and turn the electric burner on full power. Go find something to do for 20 to 30 minutes. Come back every five minutes to check the pot, but don't hang around too long. The crud on the wheel weights (road grime, tar, dog piss, etc.) will start to burn off, and the smoke is about as foul as anything you'll ever smell. Reminds me of the New Jersey Turnpike, near Port Elizabeth. If you've been there, you know what I mean. Foul.
Many casters use a lead thermometer to monitor the alloy temperature. I haven't graduated to that level yet. A good lead thermometer is $30 or more, and being the cheap SOB I am, I don't want one. The 1100 watt Walmart electric burner needs to be left on high to keep 5 to 8 pounds of wheel weight alloy in liquid form. I just set it there and leave it. It's just hot enough for eiffcient pouring. For more advanced casting with harder alloys like Linotype (printer's lead), a stronger heat source is needed. Once the alloy is molten, the steel clips and a whole lot of other crud will be floating on top of the mix. Skim it off with a spoon. Dump the skim into one of the baking pans. Remember, all this stuff is very hot, so handle it with care. Don't put it in the trash until it has cooled off. Once you've taken the debris off the top, you are left with a dirty soup of liquid metal, somewhat silvery in color, but with some black, ash-like stuff floating around. Those are impurities we will take out with flux.
Fluxing
Pouring ingots With your gloves on, pick up the pot and pour the molten alloy into the cups, until they are about 2/3 full. Pour carefully to avoid spills and splashes. Let the cups sit undisturbed for about two minutes, so the alloy can harden. After that, you can pick up the pan and move it if you are concerned about where it is resting. I usually put it on the ground (concrete) after the lead has returned to solid form. The ground helps dissipate the heat more quickly.
After about ten minutes of cooling, with your gloves still on, turn the cups over and gently tap them. The ingots fall right out. They will still be hot, and so will the cups, so be careful handling them. After about 20 minutes, they are cool enough to handle. Here's what you get:
Now we have nice, clean, nearly pure lead/tin/antimony alloy ingots that are perfect for casting bullets, in a handy size, easy to store, and easy to melt. A pound of nicely cast wheel weights goes for about a buck on eBay, so if you really want to go to town, you can sell your excess ingots for a little cash. We're ready to cast bullets.
Casting bullets
Each mold needs a handle (some molds come with handles, others require they be purchased seperately). The sprue plate is a hinged plate with a hole for each mold cavity, through which the molten alloy is poured. When the alloy has solidified, the sprue plate is opened, which cuts the excess lead from the base of the bullet. The mold is then opened and the bullets should fall out, or fall out with a gentle tap from a block of wood. It's best to have a piece of cotton cloth for the bullets to land on, or the aluminum foil bake pans can be used. The bullets are just below molten temperature when they come from the mold, so they are soft and can be dented easily. Some casters drop them into a bucket of water (with all of the safety caveats that come with such a practice...remember what I said about water near the melting pot). This is called quenching, and produces a considerably harder bullet than just air cooled bullets. Most shooters will be well served with air-cooled cast bullets, but if you want harder bullets, quenching is an easy way to get them using wheel weights. The process isn't much different than the ingots we just poured. Follow the mold manufacturer's directions for mold prep, which may involve lubricating parts of the mold, and smoking the mold with the smoke from a lighter or matches. When your lead alloy is molten, scoop some into your ladel and pour it into the mold until a puddle forms on top of the sprue hole. Wait until it hardens, about 3 to 5 seconds, then open the sprue plate and drop the bullets out. Sometimes a tap from a wooden dowel is needed to free the sprue plate or get the bullets to drop out of the mold. With some experience, you'll learn how to efficiently do all of these steps. Close the mold, pour more alloy in, and keep it up until you have the quantity you want. Keep an eye out for poorly formed bullets, which could indicate problems with alloy or mold temperature, or foreign debris in the mold. The mold has to heat up to a good working temperatue before you get consistent results, so your initial casts may produce quite a few rejects. You can put those back into the pot. Be careful not to splash molten alloy on yourself or your work area. A few minutes on prep will minimize the number of rejects.
Sizing, Lubricating Lee sizing dies come with a liquid bullet lube that is easy to apply. You put the bullets in a plastic tub, add the lubricant, and tumble the bullets around until they are coated. You then set them out on wax paper overnight to dry. Cast bullets must be lubricated, or they will leave lead in the barrel of your gun, making cleaning a real bear. I've experimented with different loads, bullets, and lubrication, and I've gotten some of the tightest groups I've shot with my guns. That's basically it. Advanced bullet casting is simply additional detail or processes on top of what I've described. Using the above info, you can experiment and custom match bullets to your guns for excellent accuracy. Or you can just make a big pile of bullets that are accurate enough to kill tin cans at 30 yards. As with other aspects of shooting sports, what you get out of it is up to you. *Edit: Since writing this article, I purchased a "previously enjoyed" Lee bottom pour lead furnace. Well worth the investment. It greatly eases the bullet pouring process. I still use the saucepan and hot plate for making ingots, and those tools are still adequate for making bullets if you are on a strict budget. Additional cast bullet resources:
Midway USA |