How much Antimony

[irgnz]

I have a bunch of pure lead, and a sorce of tin. Also may have found a sorce for Antimony.
Question is How much Antimony is too much? Want the bullets hard to push them along at around 2500fps.
Gas checks would proberly be used.
Was thinkingh on a 80-5-15% lead-tin-Antimony mix for around 25BHN.(hopefully)
Is there any advantage in going over the 25BHN?

[armyrat1970]

I have a bunch of pure lead, and a sorce of tin. Also may have found a sorce for Antimony.
Question is How much Antimony is too much? Want the bullets hard to push them along at around 2500fps.
Gas checks would proberly be used.
Was thinkingh on a 80-5-15% lead-tin-Antimony mix for around 25BHN.(hopefully)
Is there any advantage in going over the 25BHN?

If you get that BHN from that mix that's probably a lot harder than anything you really need it for. Also. What are you going to use to melt the Antimony, as its melting range is 1167.13 degrees F? Much higher than pure lead. Straight Linotype with a mix of 4% tin, 12% antimony and 84% lead has a BHN of 22. I believe it can be mixed at a ratio of 1 to 1 with pure lead to create hardball, or #2 alloy which has a BHN of around 16. This is good enough for most applications in either pistol or rifle.
If you are going to drive your bullets at 2500 you should use a gascheck. But the problem may be with such a hard alloy the bullet at that velocity may just skim over the lands and cause more leading than less and probably effect accuracy.

[KYCaster]

First, you don't have to melt the Antimony, it will disolve in lead at normal casting temps.

Second, I don't think your proposed 80-15-5 alloy will show a noticable difference when compared to Linotype, so I don't think it would be worth the effort and expense.

I use ACWW up to 2200 fps with very good results and others here report excellent results over 2500 fps with HTWW, Lyman #2 and Linotype.

Well, after a little more thought, it seems that this project would require very little effort and not a whole lot of expense. It should be very simple to add 1% Sn and 3% Sb to Linotype to get your desired alloy. If you decide to do it, keep us posted on the progress and results.

Enjoy
Jerry

[Shiloh]

IO too would like to see the results.

I will sweeten range or other scrap lead with lino to harden if needed. What I find is with the velocities I shoot, I don't need a real hard alloy. I have taken WW to better than 2100 with no problems or leading.

I use water dropped range lead for pistol boolits, there seems to be enough harder lead or lino in it to allow hardening. It workd fine up to about 1100 fps but I usually have velocities below 900 anyway.

Shiloh

My best accuracy is at lower velocities also.

[Cherokee]

KYcastrer
In its pure state, antimony will not melt when added to a tin/lead alloy. Been there, tried that. If the antimony had already been melted & blended with lead, say 50%, then it will melt fine.

[KYCaster]

KYcastrer
In its pure state, antimony will not melt when added to a tin/lead alloy. Been there, tried that. If the antimony had already been melted & blended with lead, say 50%, then it will melt fine.

The antimony I buy is certified 99%. That's as pure as I can expect for the price of bulk metal. I've been adding it to Pb, along with Sn, for many years at temps that seldom excede 700*.

Chemical analysis of my finished alloy has shown that the result was very close to my expectations.

Just as table salt with a melting temp of 1473* will disolve in 60* water, so will Sb disolve in lead.

It works just fine for me.
Jerry

[irgnz]

HI , As to the question of melting Antimony. I have a 2000 deg heat sorce that will do the job.
Idea was to melt the lead and then add a wieghed bar of antimony one drop at a time.
I am only doing this because I have over 5000(EST) bullets worth of pure lead in the shed.
I am at the moment smelting all the impurities out of it. Long process(3 melts).
I have been strugling for a year to find Linotype in this country. Even Antimony is very hard to fine, Let alone finding somone that knows what it is.
Plus I like playing with moltern metal.

[armyrat1970]

The antimony I buy is certified 99%. That's as pure as I can expect for the price of bulk metal. I've been adding it to Pb, along with Sn, for many years at temps that seldom excede 700*.

Chemical analysis of my finished alloy has shown that the result was very close to my expectations.

Just as table salt with a melting temp of 1473* will disolve in 60* water, so will Sb disolve in lead.

It works just fine for me.
Jerry

Salt, Sugar will mix somewhat with water but not completly. If after mixing you let the glass of water sit for awhile you will see salt and sugar lying in the bottom of the glass as the salt or suger is heavier than the water. As long as you keep it stirred it seems to be mixed. Antimony is lighter than lead and melts at a higher temp than lead. If you leave the mix sit for awhile the antimony will rise to the top of the melt. You have to flux and stir it back in and keep the melt stirred and mixed. If you let it sit to long the antimony will again rise to the top of the melt. You can always flux and stir it back in but it is never completly dissolved (or bonded) into the lead alloy at 700 or so degrees. If you remove it as dross, you are removing the antimony. Maybe not all but all is not melting and bonding with the lead alloy.

[Bret4207]

How long have you been casting irgnz?

[rhbrink]

I'm interested in mixing some myself cause it is nearly impossible to find in my area. The only other option is to have someone alloy it for you and then pay for shipping and then that gets really costly!

[Echo]

IRGNZ, IMHO, your desired alloy is too much/not enough. It would be brittle, and tend to shatter on contact with bone, or even just dropped on a hard floor! And toughness is another concern that few observe. If you were to use 'hard ball' alloy (2-6-92) and heat treat it, it would be plenty hard (BHN 30ish) and yet be tough enough to survive impact (bone, floor, whatever). And heat treating is really very simple, and cheap.

So. 50/50 lead/WW will be very close to 'hard ball' alloy. Heat treated, my guess is that this would go a long way toward your goal...

[armyrat1970]

IRGNZ, IMHO, your desired alloy is too much/not enough. It would be brittle, and tend to shatter on contact with bone, or even just dropped on a hard floor! And toughness is another concern that few observe. If you were to use 'hard ball' alloy (2-6-92) and heat treat it, it would be plenty hard (BHN 30ish) and yet be tough enough to survive impact (bone, floor, whatever). And heat treating is really very simple, and cheap.

So. 50/50 lead/WW will be very close to 'hard ball' alloy. Heat treated, my guess is that this would go a long way toward your goal...

Hardball Alloy is the newer version of the Lyman #2 and has a BHN of around 16. Pure lead has a BHN of around 5 and WW around 9. If you mix them 50/50 you are not going to get the same BHN as Hardball. You can by experimenting with heat treating and maybe get a hard enough alloy just from water dropping straight from the mold. Depending on what you are casting for.
IRGNZ. You didn't mention what you were casting for. I really don't think you need a BHN of 25 for your cast boolits. Sometimes TO hard is as bad as TO soft.
Check out this site:
http://www.lasc.us/HeatTreat.htm

[anachronism]

If you're alloying pure lead, start with about 4% antimony. If you want to heat treat, I'd suggest adding some magnum (not chilled) lead shot for the arsenic, plus tin. You can alloy the antimony yourself at lower temps, it just requires absolute attention to the alloying instructions. If you're interested, I have 10 lbs of antimony & the special flux required from Bill Ferguson that I don't need & would give you a good price on it.

[irgnz]

How long have you been casting irgnz?

I have been studing the art for about 2 years. After some schooling on smelting metals and alot of reading I finaly got some time to start casting 2 months ago.
So it is all a bit new although the tech side is will ingrained.

I only want these super hard pills for target shooting. Sick of having to clean every 10 rounds, with a 30 round comp.
I am loading for 30-06, and 30/30.
Looking to go down to .223 when I can find some molds.

WW are not an option, Scrap guys want to much and the tyre places won't look at me.
So I have to get my own lead, as a builder I can get Roofing flashing, Roofing nails, and lead pipe form a plumber mate.

[armyrat1970]

irgnz. Again you have to remember. If your cast bullet is to hard and you drive it to fast you will cause it to just skim over the lands and cause even more leading as the bullet is being shaved. A hard bullet is not bad but you have to find the right pressure and velocity to keep the leading down to a minimum. With the 30-06 you will have to drop your velocity down quite a bit (2,500fps or lower) and use gaschecks. You may be able to load the 30/30 without a gascheck keeping your velocity low. 2,000 fps + I would gascheck. With the 223 you are again getting into a higher velocity round and will need gaschecks with a lower velocity for really hard cast bullet.

[Bret4207]

I have been studing the art for about 2 years. After some schooling on smelting metals and alot of reading I finaly got some time to start casting 2 months ago.
So it is all a bit new although the tech side is will ingrained.

I only want these super hard pills for target shooting. Sick of having to clean every 10 rounds, with a 30 round comp.
I am loading for 30-06, and 30/30.
Looking to go down to .223 when I can find some molds.

WW are not an option, Scrap guys want to much and the tyre places won't look at me.
So I have to get my own lead, as a builder I can get Roofing flashing, Roofing nails, and lead pipe form a plumber mate.

Exactly as I thought. I mean no disrespect, but you bought the advertising hype my friend. You don't need "hard" alloy, you need good fit, just as Armyrat1970 said. If you're getting leading in 10 shots you probably have a fit problem or you're just pushing them too fast. If you want to shoot over 12-1400 fps by all means use a gas check, especially if the boolit is designed for one. Trying to shoot without a GC or paper patch over 1500 fps would be a waste of time in most guns no matter what alloy you use, and if you have poor fit it's all a waste of time to start with.

You need to start at the basics. Since you have to mix your own alloy, I'd suggest mixing something approximating WW, no more than 3-4% Antimony, maybe 2% tin. Arsenic is needed for heat treating as is the Sb, that can be found in magnum lead shot or enrichment alloy. It only takes a trace amount, less than 1/2 of 1%.

Once you have your alloy you need to determine what size boolit fits your gun. You can do that through trial and error, trying different sizes of boolits, or you can slug your bore and throat to see what the measurements are. There are pages of instructions here on slugging and determining proper fit. Start there.

I very strongly suggest you start with "plinker" loads in the 14-1600 fps area. There's a very good chance you'll find that 2500 fps target is just not needed or wanted.

[KYCaster]

Salt, Sugar will mix somewhat with water but not completly. If after mixing you let the glass of water sit for awhile you will see salt and sugar lying in the bottom of the glass as the salt or suger is heavier than the water. As long as you keep it stirred it seems to be mixed. Antimony is lighter than lead and melts at a higher temp than lead. If you leave the mix sit for awhile the antimony will rise to the top of the melt. You have to flux and stir it back in and keep the melt stirred and mixed. If you let it sit to long the antimony will again rise to the top of the melt. You can always flux and stir it back in but it is never completly dissolved (or bonded) into the lead alloy at 700 or so degrees. If you remove it as dross, you are removing the antimony. Maybe not all but all is not melting and bonding with the lead alloy.

Armyrat, what you say is technically correct, but I believe you're over-thinking the process.

When I ate lunch yesterday I had the last glass of tea from a gallon pitcher. When I drained the pitcher there wasn't any suger left in the bottom. When I emptied the glass there wasn't any sugar left in the bottom. Why???? Because the amount of sugar I put in the tea was nowhere near the saturation point; the sugar was completely disolved in the tea, it was in SOLUTION. When you excede the saturation point then the excess is in SUSPENSION and will stay there only as long as it's stirred. When you stop stirring the excess will precipitate out and what's in solution will stay until something is done to change the saturation point.

Antimony in Lead is very similar. The saturation point of Sb in Pb is ~3.5% and any more than that will precipitate out, even when its in a solid state.

But, add Tin and everything changes. One of the benefits of Sn is that it helps keep the Sb in solution. I admit that I don't know what the saturation point of Sb in Pb-Sn alloy is, but Linotype with 12% Sb is a very stable alloy and doesn't lose any Sb through precipitation.

Once disolved and in solution, it will stay there unless something changes to cause the saturation point to change.

Like I said before, It works for me. It's a simple process. It doesn't require any exotic equipment. It gets the desired results. It gets the EXPECTED results. So where's the problem?

Jerry

[oso]

Well irgnz, there seem to be some strange thoughts expressed in this thread. I suspect you have the training and already enough experience to sort it out. Having done it both ways myself, I'll just say I prefer to dissolve antimony by submerging it in the lead/tin melt than work with molten antimony.
The advantage with higher BHN is that it makes things easier, that's why jackets are popular some places. Just don't make your boolits so small that you have skimming bore riders.

[irgnz]

Well irgnz, there seem to be some strange thoughts expressed in this thread. I suspect you have the training and already enough experience to sort it out. Having done it both ways myself, I'll just say I prefer to dissolve antimony by submerging it in the lead/tin melt than work with molten antimony.
The advantage with higher BHN is that it makes things easier, that's why jackets are popular some places. Just don't make your boolits so small that you have skimming bore riders.

The coments on here are interesting, It was, and is the responce I hoped for.
Only thing to add at this stage is that the load I have been using is quite accurate.
1,1/4" group 5 shot. Very respectable. just starts to blow out after shot 6-7.
Always good to get a broad side of opioun, It is a shame that casting is not so popular here, there are a few that do it but most are not keen to spreed the word.
Cheers all I wil keep you informed of progress.

[HangFireW8]

WW are not an option, Scrap guys want to much and the tyre places won't look at me.
So I have to get my own lead, as a builder I can get Roofing flashing, Roofing nails, and lead pipe form a plumber mate.

Old timers, take note. This is the new reality. WW are not always commonly available, and therefore not always the best option, or even an option at all.

-HF