Softening Alloy

[GregLaROCHE]

Most are trying to harden up their alloy, but I would like to soften mine up. I have an abundance of range scrap recuperated from a 25 meter range. It’s an indoor cast bullet only club. Not many members cast their own and use commercial lead boolit rounds or buy slugs for reloading. I’ve come to find that the lead used is normally pretty hard so it’s easy to transport without it getting damaged.

The hardened lead I was recuperating worked well with rifle boolits, but now I have have been doing a lot of muzzleloading where it is best to use soft lead. I am in France, so unless someone here would like to trade some soft for hard, postage puts that out of the picture.

I am wondering if it is possible to remove the alloy, that increases its hardness. I guess I could cook off the tin at a high temperature, but how about the antimony, that I think will need higher temperatures. I’m hoping there is something I could flux with to bond the the antimony letting me remove it. Are there any metallurgists that can shed some light on this.

Thanks

[bangerjim]

Copper sulphate (root killer - in the plumbing department of a big box) takes out Zn, Sn, and I do believe Sb, although I have never verified the latter. It does work for Zn removal.

Put some on top of the melt, mix it in after it turns white (moisture all gone) and let it do it's thing.

banger

[centershot]

Greg, I don't believe you'll be able to remove or reduce the antimony content with any means available to you or me except by adding lead. You certainly do not want to cook off the tin in that alloy! Tin doesn't contribute nearly as much to hardening as does antimony. If the bullet companies in France are using anything similar to the "Hardball" alloy used in the states, most likely your range scrap is 92-6-2 or thereabouts. If you can get pure lead you could mix up a pretty soft alloy for pistol boolits, might be a little hard for your muzzle loaders but I hear a lot of guys over here say that COWW works fine for theirs. I prefer pure lead, but sometimes circumstance has it's way with you.

[GregLaROCHE]

I’ve used a harder round ball with a patch in a smooth bore and it seems to work fine. I have an Enfield that shoots hollow based conical boolits. Pure lead is recommended because it’s working on the principal that the explosion forces the bottom (skirt like base) out to make a seal with the bore. Another gun I have relays on the ball being close to the groove size and the rifling gets cut into the lead. If it is pure lead, it’s a lot easier to force it down. That’s why I am looking for as pure/soft lead I can get.

[Winger Ed.]

You may need to just sort the range scrap better.
You can usually spot the swaged bullets in with the cast ones, then pull them out, and melt jacketed ones with the swaged.
The little .22s might come out with a sifter.

Without some special equipment & such, It gets a little more involved to 'un-alloy' Lead.

[243winxb]

If you bring the pot temperature up very slowly, just to the point when alloy becomes slightly liquidus, the antimony will be on the surface. Do not flux. Skim it off the top. Copper will be there also. Should look like oatmeal.

[Wilderness]

You may need to just sort the range scrap better.
You can usually spot the swaged bullets in with the cast ones, then pull them out, and melt jacketed ones with the swaged.
The little .22s might come out with a sifter.

Without some special equipment & such, I don't think it's practical to 'un-alloy' cast boolit.

Greg: When melting what you think is non-soft scrap, watch for the ones that float on top before melting, and fish them out - straight lead has a higher melting point than antimonial lead. A hollow base in a pistol bullet speaks also of softness (and swaging).

[GregLaROCHE]

You may need to just sort the range scrap better.
You can usually spot the swaged bullets in with the cast ones, then pull them out, and melt jacketed ones with the swaged.
The little .22s might come out with a sifter.

Without some special equipment & such, I don't think it's practical to 'un-alloy' cast boolit.

The problem is it’s an indoor range with a metal backstop and the boolits are very flattened and smashed up. It’s just about impossible to tell what they were. I do collect from the 50 meter range where mostly muzzle loaders and 22s are shot and the lead from there is much softer, but not as soft as pure lead. I think some of the 22s must be hardened lead too. There’s also a lot less of it. If there’s no way to soften the alloy close to pure, I’ll probably just have to find another source.

[Dusty Bannister]

Any pellet gun ranges in the area? That might provide enough soft lead to dilute some of the hard range lead.

[Old Caster]

I would not use any bullet with antimony in it. One of the BPCR guys did some experimenting with lead that was harder hoping for better accuracy and his problem was that when you get leading with no antimony it is simple to clean it out with a patch and just soap and water. If the alloy has antimony in it, you don't get the larger clunks that will clean out but a smear inside that can have black under it which will cause rust because you will think it is clean when it isn't. He messed his barrel up with it. If you use a patch with a round ball, it may be OK but I would not try it because of the possibility. To understand what I am talking about, take a wheel weight and rub it on a piece of steel and you can even write your name. With pure lead or lead and tin mix, you cannot.

[Wayne Smith]

Sorry Greg, but once an alloy always an alloy. You can dilute the alloy but you can't unalloy.

[Larry Gibson]

Sorry Greg, but once an alloy always an alloy. You can dilute the alloy but you can't unalloy.

Wayne is correct. I have a considerable amount of similar range alloy recovered from indoor ranges. It has a high antimony to tin ratio. First i dilute the alloy with lead. I use 30 to 60% depending on how soft i want it to be. I then add 2% tin to the mixture which casts much better bullets, more ductile bullets and gives less rejects. A little casting and BHN testing after the bullets have aged 48 hours if WQ's and 14 +/- days if AC'd.

[PBaholic]

I am wondering if it is possible to remove the the antimony. Are there any metallurgists that can shed some light on this.

Aerate the alloy, just above it's melting point, Lead Oxide and Antimony will come out of the mixture and sit on top of the alloy. Simply skim this off, like you would Dross with a spoon.

By aerate, I mean more than just stirring it, as stirring will also allow Antimony to dissolve back into the alloy. I'm thinking more like the beater of a mixer on a drill. You'll need to experiment with whatever gives you the most Dross, as this only occurs to me as a by-product of my alloying, which I'm actually trying to avoid. In my case, I refine this Antimony Dross, and dissolve it back into my alloy.

For those wondering how to dissolve Antimony back into your alloy, place it in a coarse screened basket, and submerge it in your melted alloy. Move this basket around, but not vigorously.

The way you'll know if it's Antimony, is heat this Dross to try to melt it. Antimony will just barely melt with a propane torch, and glow slightly red in it's liquid state. Your Dross will contain some lead oxide, which will easily melt back into lead. Pour the easily melted portion of the Dross off, to get down to the Antimony.

I use an thin aluminum pan and a propane torch, and maybe a few tablespoons of this dross. As if you are a chef, toss the lead around in the pan to aerate it more, and keep pouring off any silvery metal. Toss it around, heating it with the torch. It will look almost like dirt. When you get down to a dry, coarse substance, that you can tap down with a spoon, and turns yellow with the torch directly on it, and can be barely pooled into a liquid that glows red, this is mostly Antimony. Antimony will easily stick to your spoon.

Be careful, as Antimony is Very Toxic in this state. This should only be done in a ventilation hood. If you don't own a hood, make one. This is VERY important!

[405grain]

You need to get some lead. Save the harder alloy for something else, but shoot lead in your muzzle loader. If you try softening the alloy it might still be too hard for proper skirt expansion in your Enfield. The result will be poor bore seal, less accuracy, and possibly even bore leading. See if you can locate a source for pure (or nearly pure) lead. Is there a dentist office near you? See if you can get some of that lead foil they use for xrays. Is there a skeet range near by? Can you get reclaimed shot from it? If I remember correctly lead shot is 98% lead and 2% arsenic. Do roofers in your area use lead skirting on roofing jobs? Will they sell you the junk lead that they strip from old roofs? Is there a scrapyard or wrecking yard near by that sells lead?

If you can find a source for lead then you've hit the jackpot! The hard alloy that you're recovering can be used for rifle boolits. Your hard alloy can be cut with lead to make pistol boolits. The straight lead can be used for muzzle loaders. You'll have all the bases covered.

[murf205]

Sorry Greg, but once an alloy always an alloy. You can dilute the alloy but you can't unalloy.
So I am guessing that this goes for zinc in a contaminated pot too, right?

[bangerjim]

So I am guessing that this goes for zinc in a contaminated pot too, right?

NO. WRONG. Please read my post #2 above. It is like nobody read it, what with all the replies posted above!!!!!

You can remove Sn and Zn from a lead alloy ("un-alloy" if you want to call it that) by using several methods, one I list above. I have not tried Sb, but give it a try. I have never seen the need to remove Sb form my alloys I use. I do not shoot roundballs with black powder.

[murf205]

NO. WRONG. Please read my post #2 above. It is like nobody read it, what with all the replies posted above!!!!!

You can remove Sn and Zn from a lead alloy ("un-alloy" if you want to call it that) by using several methods, one I list above. I have not tried Sb, but give it a try. I have never seen the need to remove Sb form my alloys I use. I do not shoot roundballs with black powder.

Ok, so how much to use in a pot with around 17 lbs in it? Tea spoon? I've never done this so I'm treading in new territory in hopes of salvaging a mix of WW that got some zinc it it.

[Dusty Bannister]

Whatever you do, do it outside. Safest way is to just dilute it. Pour 1 pound ingots. In 17 pots, the stuff is gone adding one pound per pot.

[BattleRife]

The development of extractive metallurgical circuits to separate one metal from another is extremely complicated business, whole companies are dedicated to researching and engineering these processes. Even if you figure it out, it requires full control of the process variables (temperature, gaseous partial pressures, chemical activities of the major reactants) to make sure it happens reliably. Way easier to just go find a different source of lead, especially if you are in Europe. It's my understanding you guys are standing amongst a thousand years of lead infrastructure over there, from water mains to chapel roofs.

[Green Frog]

I think we've established that A) the only way to soften a lead alloy is by adding a bunch more lead, and B) once antimony is alloyed with lead, it is very impractical o de-alloy it.

At this point, I would suggest you might try to find someone who is casting rifle or high performance pistol bullets and arrange a trade. If you find enough pure lead to do you any good with diluting your hard alloy, then you'd be better off using the soft lead as is. A tiny amount of hard alloy will quickly make your mix harder than is desirable for muzzle loaders. I proved this to my chagrin when I accidentally ran a batch of Minie Balls using a hard linotype mix. Not a good idea! I don't know how hard lead would work with patched round balls, but wouldn't waste time trying it.

When it comes to muzzle loaders, I'm afraid there's just no substitute for good old fashioned lead.

Froggie

[GregLaROCHE]

Copper sulphate (root killer - in the plumbing department of a big box) takes out Zn, Sn, and I do believe Sb, although I have never verified the latter. It does work for Zn removal.

Put some on top of the melt, mix it in after it turns white (moisture all gone) and let it do it's thing.

banger

I’m considering giving this a try. Pretty much out of curiosity. I can buy copper sulfate online, which is the easiest for me. Is this the type of copper sulfate that will work? If you enlarge the picture of it, everything is written in English.

[243winxb]

My post above , was from an NRA article on how to remove copper. Melt alloy in pot. Let fully cool. Reheat as said above.

[bangerjim]

I’m considering giving this a try. Pretty much out of curiosity. I can buy copper sulfate online, which is the easiest for me. Is this the type of copper sulfate that will work? If you enlarge the picture of it, everything is written in English.

Any copper sulphate that is advertised as "septic tank root killer" will work. I get it at Lowe's, a mile away. Any plumbing supply store (even Ace hardware) should have it in stock. I have only used it for Zn removal and found it works, but removes Sn too, and probably Sb. When I was done with the batches I treated, I had pretty much soft lead left, from 12 down to 6 hardness, probably with a bit of Cu in it from the chemical reactions. Cu makes your alloy tougher not harder.

Please feel free to try it and let us know on the Sb removal.

I used at least 3 teaspoons in a 10# experimental batch pot. Be sure you cook off all the chemically entrained water and the blue crystals have turned white before stirring.

Good luck!

banger

[PBaholic]

I think we've established that once antimony is alloyed with lead, it is very impractical to de-alloy it.

It's not impractical. Everytime you melt your alloy, some of the Antimony comes out. This happens whenever air reacts with the alloy. If you Aerate the alloy, you'll get more of this reaction.

I guess you guys need pictures.

The powder is mostly Antimony Tri-Oxide, although there is still other things mixed with it. It has already been gravity washed to remove any dirt and lighter substances.

The rocks are mostly Antimony and Antimony Tri-Oxide. This is what you get when you heat the powder with a propane torch. Note you can't actually melt this with a propane torch, but you can get it to stick together. I use the propane torch, as any lead oxide still left in the mix will melt and you can pour it off. This poured off lead is VERY hard, so it's not just lead either.

The mass in the upper right corner, is when you use an acetylene torch. Everything will melt together into a solid mass.

Be aware, I'm not trying to remove the Antimony. I actually put it back in my alloys after I refine it.

[GregLaROCHE]

I finally received real “Root Destroyer” 99% copper sulfate from the US. I am ready to do an experiment to see how it effects hardness of alloys. I plan to melt around ten pounds of my range scrap ingots in a Lee twenty pound bottom pour pot. I will cast several 500 grain boolits first and then add the copper sulfate. I will cast more boolits after the alloy has been treated. Finally I will compare the hardness of the boolits before and after with a Lee hardness tester.

How much copper sulfate should I add to approximately ten pounds of lead?
What next? Stir and wait how long?
What about fluxing with sawdust or beeswax?

Give me some ideas of how you think I should do it. Thanks.

[243winxb]

Sulfuric acid is listed in the sds of Root Destroyer” 99% copper sulfate.

[Martin Luber]

I am surprised that your 25 meter lead is hard. It's usually 22s and 32 s&w which is soft. What are they Shooting that is hard? Eley white boolets (Tenex etc) are 1% antimony whereas black are 0.1

[GregLaROCHE]

I am surprised that your 25 meter lead is hard. It's usually 22s and 32 s&w which is soft. What are they Shooting that is hard? Eley white boolets (Tenex etc) are 1% antimony whereas black are 0.1

A lot of handgun boolits I think. The 22s are mostly shot at 50 meters. The lead there is softer, but there’s a lot less of it and it is harder to collect because of a different type of backstop.