Mystery metal in wheel weights?

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Correia

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I was casting some some bullets the other day. The lead came from melted down used wheel weights. The lead was melted down into a big pot, skimming off all of the clips and that kind of thing, and then poured into ingots. The ingots were dropped one by one into the caster.

The temperture seemed to be okay, but we were still getting some frosting. Usually around the center band of the bullet. (200 gr. .45 SWC) Playing with the temp a little bit did not really change that.

Then the spout started getting clogged. Cleaning out the caster, a brittle crumbly metal was found. It seemed to be heavier than the lead since it sank to the bottom, and it may melt at a slightly higher temp, since it did not really clog the spout until I turned down the temp due to the frosting.

So does anybody know what this stuff is? I made up about a thousand bullets before this discovery. Most of them look just fine. I've set aside the frostiest ones for future testing, but before I do that I wanted to see if somebody here had an idea.
 
IME, you can get a bit of dross in the spout of a bottom-pour furnace, caused by the presence of oxygen down there. The stuff doesn't "sink" down there, but is generated there by normal casting operations.

Drop some fo that mystery metal on the top of your lead pool and see if it sinks. If it does, perhaps it's tungsten (don't know the melt point offhand) or some odd isotope of something else...?:uhoh: ?

If it doesn't sink, don't worry about it and add a big paperclip to your casting equipment like I did. Quick way to unclog.:)
 
Its Antimony.

Its what makes wheelweights the good metal for bullets that it is.

Re; frosting on middle driving bands and "clogging". I too see this, especially when casting "Keith" style Semi-wadcutters.

Try this:
1. Cast bullets at higher temp than you normally would. The antimony in wheelweights will cause what I've seen others call " cold frosting". Very indicative of a high antimony alloy with a low tin ratio.

2. Smoke the inside of the mould cavity with either a match or a butane cigarette lighter. This too will reduce "cold frosting".

3. Add some "lead-free" solder of 95/5% Tin to Antimony to the melt. This addition of Tin will reduce the slag buildup. Be wary of the "silver-bearing" lead-free solder. This works good too, but too much will result in a "blue" skim of silver and this can cause similar problems to what you've described with your melt.

4. When orfice of Furnace clogs, hold a butane lighter flame under the orfice until it starts dripping again. Then run a stream of lead into "catch container" for 3-4 seconds to clean and reheat the orfice to casting temperature. If this dosen't work, time for the "PAPER CLIP" !

I like to cast my bullets on the "hot" side, as over 99% of my casting is done with W/W metal, either from W/W or range scrap containing mostly my previous fired bullets of W/W. By casting them where they drop out "Shiny", and then lightly frost upon cooling, I get the best bullets.

How good? The last batch of .452" 255gr FN bullets I cast, when loaded over 6.5gr and 7.5gr of Win. 231 in .45 Colt- lubed with 50/50alox, gave groups under 1.5" at 50yds from my Win-94 rifle. Usually 4 in 1 hole, and a single flyer opening group to 1.25"
With my Marlin/Glenfield mod30 in .30/30, a 160gr FNGC over 32.0gr of RL-15 will group 1" at 50yds all day long, at 2,150fps.

As long as the "hot" frosting is not extream, it dosen't affect accuracy. In the Lee manual, they recommend this procedure as well, especially with their "Tumble lube" moulds.

However, I had used it for years SINCE back the mid '70's when I was starting bullet casting.

Hope this works for you too!
 
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