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DragoonDrake
10-14-2008, 04:38 PM
Hello all

I have a question for those better than myself here. I have stumbled upon a small quantity of pure antimony and i know that is what is used to harden, water-quench bullets. I tried to make a batch of hardball equivalent lead alloy (2%tin, 6%antimony, and 92% lead) and I was unable to get the antimony to melt and flux/mix in.

What am I doing wrong and if nothing, then what can I do differently? I am using a Lee 20lb bottom pour pot and I let the alloy '"cook" for over an hour at the hottest setting.

Help me please

Adam

nighthunter
10-14-2008, 04:56 PM
There used to be a site called WWW.theantimonyman.com and he explained how to get antimony into your melt. Try the link and see what you get.
Nighthunter

oso
10-14-2008, 05:14 PM
You can dissolve antimony pieces into a lead + tin melt at normal casting temps as the antimony forms an inter-metallic compound with the tin. The trick is to submerge the antimony chunks in the melt or it just floats on the surface. I perforated the bottom of a can that fits the pot and made a wire handle to move it up and down for agitation while dissolving. I wouldn't mess with antimony dust.
To melt antimony I've used a charcoal furnace with blower - more trouble than it was worth.

runfiverun
10-14-2008, 05:27 PM
i hold the temp around 600* and flux it in. and stir. marvelux will do for a flux.
just a dash of marvelux and a pinch of antimony at a time.

bruce drake
10-14-2008, 07:19 PM
Welcome to the Forum!

I note the last name and I assume from the front half that you are or were a trooper with one of the Cav Regiments?

Don't know if we are related by blood but we are related by our interest in casting.

Bruce

(My Family is from Maine originally)

KYCaster
10-15-2008, 12:30 AM
OK...grab a cuppa coffee and a donut, this is gonna take a while.

This question comes up pretty regularly here and usually gets plenty of responses. If you want the real skinny on Antimony, call up Bill Ferguson, The Antimony Man, and ask him....be prepared to spend a little time with him cause he'll talk as long as you want to listen. What that man has FORGOTTEN about metallurgy would fill several volumns.

I used to buy quite a bit of Sb from Mr. Ferguson and have talked to him many times about using Sb in boolit alloys. The last time I spoke with him (about two years ago) I got the impression that his health was failing and that it was becoming a chore for him to continue his business because he is no longer able to do the physical labor required to process and package the product. He said he was waiting for his nephew to help him with some orders and gave me contact info for another supplier.

I think I'll give him a call tomorrow just to see how he's doing. He's a fine gentleman with a wealth of knowledge he's willing to share with anyone who asks.

ANYWhooooooo...he sells Sb and the flux that he developed to help alloy it into your boolit metal along with the instructions to do it, and with his help I have developed a process that works very well for me.

The biggest problem I had to deal with was the flux. Bill will tell you that his flux is hygroscopic (attracts water). In the Dessert Southwest where Bill is, that's not a problem, but here in the Ohio River Valley where the humidity rarely gets below 60% it's an entirely different story. Least bit of moisture in the flux and when you put it in the melt you get a foam that encapsulates the Sb and doesn't let it dissolve, so I've found that other fluxes work just as well....BTW...you don't need to melt the Sb, it will dissolve in the liquid lead, just like NaCl (salt, with a melting point of 1473F) will dissolve in water.

The flux that works well for me is boolit lube. I use lots of Thompson's Blue Angel so that's what I flux with. I don't know if other lubes will work as well, but I don't see why not. I recently got some acid core solder that I add to increase the Sn content and it seems to work very well as a flux. How you add the flux, I think, is important to the process.(more about that later)

Bill has determined that this process works best when the Sb is a uniform size, so he crushes and screens it to remove the undesirable sizes and sells you the optimum size...+1/8 -3/8...it falls through a 3/8 mesh screen but doesn't fall through a 1/8 mesh screen. This is by far the easiest size to deal with but I've used both larger and smaller sizes with good results. I once bought all the fines that Bill had sifted out of his product and used it without any problems and I don't bother screening...anything that looks ~3/8 or less goes in the pot, doesn't seem to make any difference.

OK...here we go...you got yer base metal...Pb, WW, roof flashing, whatever. You know how much Sb is in there already...right???...right??? Yeah, sure...anyway, you know how much you want to end up with so you weigh your base metal and your Sb and you throw the base metal in the pot (allow for dross) and light the fire.

Melt the base metal and flux it till you have clean metal to start with. Any garbage you have in there is just going to make this job a whole lot harder.

I usually add the Sn now...doesn't matter you can add it after you've done the Sb, then spread the Sb more or less evenly over the surface of the melt and immediately add the flux.

Listen up now cause I'm only going to say this once..........HOW YOU ADD THE FLUX IS THE KEY TO THIS PROCESS. You need to add enough MASS to the melt to reduce the temp. to the slushy stage, and part of this mass needs to contain flux (boolit lube). I use boolits culled from the size/lube stage of the opperation plus other culls and ingots of the base metal if I don't have enough culls to do the job. If you keep a close eye on your melt temp. then ~5% or so of the total weight of the melt should do the job.

THE LOWER THE TEMP. THE FASTER THE Sb WILL DISSOLVE. Even if the melt freezes completely, that's OK. As the temp. increases, stir constantly until the Sb is completely dissolved or the flux is completely consumed. If you still have undissolved Sb, then add more flux/metal to reduce the temp. and stir some more. If you still have undissolved Sb, turn off the heat and fire it up again tomorrow. If that doesn't work then you gotta try a different system.

MORE ABOUT THE FLUX...When you add enough metal to the melt in the form of lubed boolits to reduce the temp. of the melt, it will form a "glob" of metal which will sink to the bottom of the pot because it is colder than the melt (hotter metal rises), thereby releasing the flux below the surface of the melt. I may be all wet here, but I think that's what makes this work.

I've been using this process for about fifteen years and I've had scrap metals and my finished alloys analysed enough times that until recently, I've been confident that I could very accurately predict the composition of my boolits. Lately, though, there have been enough imported products in the system that the old standards no longer apply.

Like Uncle Ray, The Carpetman says, "When you start with scrap of an unknown composition, how can you expect to get an exact alloy?"

I hope this answers some of your questions.

Jerry

DragoonDrake
10-15-2008, 12:48 AM
Thank you all so very much for your help and answers. I will be able to these methods and tips on Thursday or Sunday depending on what day I get off. Once I do I will let you know how it went.

Thank you all again.

Adam R. Smith

Sorry Drake, my screen-name is a nick name. Also no relation to the economist.

Lloyd Smale
10-15-2008, 06:56 AM
ok i tried this stuff once. I added enough antimony to get the percentage i wanted and got it melted in and then added my tin to come up with an alloy that was suppose to be about the same as lineotype. I got an alloy that would cast a bullet that was grainy and seemed harder then it should have been the alloy didnt cast well and no matter what temp you casted at the bullets came out a dull colar. I never got those bullets to shoot well either. Now before someone says i had to much antimony in the mix all the measurements were checked on a certified scale. it was like the antimony was in the mix but just wanted to stay seperate. I dont know how better to explain it. I tried this 3 different times and just gave up figureing it wasnt worth the bother.

44man
10-15-2008, 08:36 AM
I use 20# of WW's, 6.4 oz of tin and 9.6 oz of antimony chunks plus the flux from Bill.
Bill explains that you need to be very carefull you don't add too much flux or it will foam. He says to use a salt shaker. If you get too much flux you might have to let it all cool and wash the flux off with water.
It has worked great for me for years and just holding at 600* while I slowly stir the antimony under the surface. All that is needed is a thin film of flux on each piece, too much takes longer.
All you need to do is ask bill for a formula to make what alloy you want with what you are starting with.
My boolits are shiny, water drop to 22 BHN and are tough and accurate.
I have put too much flux in once so I just used the spoon to scoop as much as I could off the surface. It tames down.

CZShadow
04-01-2011, 07:37 PM
Hi guys.
Sorry to bring this up since 3 years ago, but I think this IS the right place for my questions.
I'm about to start casting my own "boolits" for my reloads. I've ordered several molds, and a ladle from Lee. I'll be casting 9mm, 40S&W, 45ACP and 44 ojival bullets for a Remington 1857 by Traditions.

Wheel weights? I tried to get used WWs in the tire stores, but it seems the recyclers are fast and have already agreements to pick up all the used stuff. So, I decided to get my own raw material. Picked up the phone and yellow pages, drove across town and got me these:

http://i180.photobucket.com/albums/x317/LopezLandauro/Coleccion%20de%20armas/IMG00419-20110320-09221.jpg

I got almost 24 kilos of pure lead, tin and antimony (pictured in that order). I wanto to end up with an alloy 90-5-5, similar to Lyman's #2, or perhaps a recipe with less tin, since it's really expensive (would 93-2-5 work?)

Some web searching before I light up the fire showed me my first challenge: antimony melts at a much higher temperature that lead and tin. So more searching got me here.

Very interesting input from the forists, specially KYcaster. But I have a question:
Will Lee's boolit lube work as flux in this case? I've read in LA Silhouette Club's website that sawdust is also a good flux, would that work for the antimony? What about candles?

Thanks for the answers, regards.
Rod

runfiverun
04-01-2011, 08:25 PM
don't use thee alox.
candle wax will work with the above suggestions jerry made.
the temp below 610 is key.
i have used bill's flux and marvelux both, but i flux my smelting alloys with candlewax and sometimes use sawdust also. i wouldn't use the sawdust for the ore though.
you need an oxygen free zone to alloy in the oxides.

the 1857 will most likely do much better with pure lead if it's a front stuffer.
the others will do fine with a 1% tin and 3% antimonial alloy. @11 bhn
the 9 and 40 most likely will want a harder alloy but you can waterdrop the 1/3 alloy.@18 bhn

shotman
04-01-2011, 08:36 PM
melt your lead and other stuff FIRST and flux some as run said NO to lee stuff wax as ok bring temp up and add your ANTY it will float for a little while but will break down and mix. flux again and make your ingots
would be best if you got some bee wax from Randyrat here it works best for me making my own He is in vendor section

CZShadow
04-02-2011, 11:57 AM
...you need an oxygen free zone to alloy in the oxides...

Do you mean I should start in a closed room, no windows or door opened, no outdooors work? Isn't that kinda bad or hardazous? I mean, I can cover my mouth and nose, is that what you mean?


......but you can waterdrop the 1/3 alloy.@18 bhn...
I was planning on dropping the cast boolits into a large pot, full of cool water, with a partially submerged cloth to hold them and not letting them hit the bottom, as I saw in youtube, is that what you mean, right? I don't understand what you mean by "the 1/3 alloy", can you please explain?

Thanks you guys.
Rod

GLL
04-02-2011, 01:09 PM
Buy "Super Hard Alloy" (30%Sb+70%Pb) from Rotometals and be done with the headaches! The end cost is about the same ! :) :)

The best part is you end up with an exact known composition !

http://www.rotometals.com/Bullet-Casting-Alloys-s/5.htm

Jerry

runfiverun
04-02-2011, 01:29 PM
to turn oxides back into an alloy you need an oxygen free barrier on top of the alloy.
the flux will do this for you,
marvelux forms a glass like cover on top of the alloy and it pulls metals into the glass covering bad as well as good metals. it however will allow you to get the ore to flux in.
the candle wax will cover the alloy also, creating this barrier, it may also burst into flames.
when adding the ore to the alloy be prepared to stir constantly, don't overuse the flux and donot overload the pot with the ore.

the 1/3 i refer to is 1% tin and 3% antimony and the other 96% is lead.
most any time you see numbers like 2/6. 4/12. it refers to tin/antimonial ratios.

L1A1Rocker
04-02-2011, 02:00 PM
Some good information here. Thanks folks.

CZShadow
04-02-2011, 11:24 PM
Yes, thanks a lot!

pistolman44
04-02-2011, 11:48 PM
The way i do it is use a propane torch on it over a pot of melted lead. Just melt it into the melted lead. Works for me.

lwknight
04-03-2011, 08:05 AM
A little tin in the lead makes the antimony stay disolved and behave like it is part of the plan. Without some tin the antimony oxidizes easily and in high percentages will even make a floaty slush. It has been my experience that about a 3 to 1 antimony to tin ratio works best for a smooth lovely alloy that stays evenly mixed..

GSSP
11-25-2018, 09:07 AM
Ok, sounding board, so here goes.

Goal is a 96-1-3 mix giving 11 BHN. I have 600 lbs of 1/8" thin X-ray barrier pulled from the walls of a hospital X-ray room walls; I believe it is pure lead. 30 lbs of Tin Cut Wire Pieces 30 Pound Box 99.9% Pure ....and..... 30 lbs of Super Hard Alloy Metal Nuggets -(30%-Antimony, 70%-Lead)

In a very ventilated area (mouth of my open garage with the near constant canyon winds blowing fumes away from me), bring pure lead up to 600 deg F. With the Marvelux or pure beeswax I have on hand, add enough flux to have a thin film (glass surface?) over the lead. Add the tin then mix well, bringing the temp back up to 600 deg F. Repeat with either flux (glass surface) and add the Super Hard so the flux incapsulates each piece of Super Hard to coat each piece as I gently drop into the molten lead. Constantly stir until temp comes up again.

Hopefully, I got it right. One additional question is how much SuperHard to add. Since it's a 30/70 mix of SN and PB) should I multiply by 3.3? Example....If I need 1 oz of SN would I add 3.3 oz of SuperHard?

This inquiring minds needs to know. Thank you.

Alan

whisler
11-25-2018, 08:34 PM
"One additional question is how much SuperHard to add. Since it's a 30/70 mix of SN and PB) should I multiply by 3.3? Example....If I need 1 oz of SN would I add 3.3 oz of SuperHard?"

You have your symbols confused. Superhard is 30% Sb (antimony) not Sn (tin).