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irgnz
03-30-2009, 03:23 AM
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
03-30-2009, 03:41 AM
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
03-30-2009, 11:02 AM
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 :drinks:
Jerry

Shiloh
03-30-2009, 11:26 AM
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
03-30-2009, 01:05 PM
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
03-30-2009, 06:54 PM
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
03-30-2009, 06:56 PM
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
03-31-2009, 06:30 AM
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
03-31-2009, 06:39 AM
How long have you been casting irgnz?

rhbrink
03-31-2009, 06:52 AM
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
03-31-2009, 04:08 PM
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
04-01-2009, 04:40 AM
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
04-01-2009, 08:22 AM
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
04-02-2009, 02:50 AM
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
04-02-2009, 06:44 AM
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
04-02-2009, 07:38 AM
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
04-02-2009, 11:41 AM
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
04-02-2009, 03:38 PM
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
04-02-2009, 08:24 PM
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
04-02-2009, 09:55 PM
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

HangFireW8
04-02-2009, 10:32 PM
Was thinkingh on a 80-5-15% lead-tin-Antimony mix for around 25BHN.(hopefully)
Is there any advantage in going over the 25BHN?

I'll find out soon, I got there without exactly trying.

After a first poor attempt at alloying pure antimony, and ending up with 12BHN ingots, I put all my scrap bullets and lead together with the oxidized remains of my antimony alloying attempt, and ended up with ingots at BHN 18-19. Hmmm. I was figuring around 9 or 10 BHN.

Casting them for 30 cal later and dropping them in water, I found that hardness of the non-frosty boolits was 21 BHN, nicely frostly was 30 BHN, and the partly frosty in between. While exciting, I ended up having to sort by frostiness. Obviously, all these boolits are not going to behave the same as they are not all the same hardness.

I am loading them in 3 batches, ~20, ~25, and ~30BHN. Fortunately the vast majority are in the last batch. All are gas checked.

I am also under no illusion that they will maintain 30 BHN. I will shoot them all within a month or two.

Anyway, the point is, if you go for super hardness, you'll have to watch your alloy temp and water tempering carefully for consistency, sort and load accordingly, and use them in a reasonable period of time before they age soften.

-HF

anachronism
04-02-2009, 10:56 PM
For the best consistency, heat-treat your bullets instead of water dropping them. This way all the bullets will be the same temperature when quenching in water of the same temperature.

armyrat1970
04-04-2009, 05:36 AM
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

KYcaster i agree with you on some points. Check this site:
http://www.lasc.us/CastBulletAlloy.htm
Read down to when it explains Antimony in the alloy.

Bret4207
04-04-2009, 08:55 AM
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

True. Sad, but true. Still, if you're going to be mixing an alloy there is really no reason not to mix an alloy similar to WW, maybe with a bit more tin to aide fill out. WW is about perfect for 95% of the shooting most people do- plinking, target and hunting up to deer sized game. With the addition on a bit of Sn or Sb and some heat treating you can produce an alloy capable of almost anything a lead alloy boolit can do.

IMO the super hard alloys, those above 18-22 Bhn, are needed only for relatively few areas. Yes, there are the occasional barrels that just work better with them and high pressure/velocity sometimes requires super hard alloys. The extreme alloys over 30 Bhn...why not just use Zinc? It's readily available, can be cast using the equipment we have now and there ahs been some successful work done with it.

Just a thought.

KYCaster
04-04-2009, 11:38 AM
KYcaster i agree with you on some points. Check this site:
http://www.lasc.us/CastBulletAlloy.htm
Read down to when it explains Antimony in the alloy.


Armyrat, There is a lot of good info on the LASC site, I refer to it often. I've read the article you cited several times before and agree with most of it, but there are a couple of significant errors in the text so, like everything else we hear or read, we have to try to separate the wheat from the chaff.

Quote from the article: " Heat treated lead, unlike steel, does NOT surface harden but achieves the same BHN all the way through." This doesn't have anything to do with Pb-Sb alloys, but I include it just to make my point. Precipitation hardening steels do indeed achieve the same hardness all the way through. Iron and mild steel can be surfaced hardened by heating in the presence of hardening agents such as Carbon or Nitrogen which results in a thin, hard surface layer.

Another quote: " Antimony can be purchased online from the “Antimony Man” but with its high melting point it is a somewhat arduous task trying to alloy it with lead. The Antimony Man supplies instructions on alloying antimony with the purchase that include the warning that the instructions must be followed precisely to be successful. In addition, antimony is extremely toxic, when handling it in a powdered form proper breathing protection and proper clean-up techniques of surrounding surfaces should be used." The instructions that Bill Ferguson supplies with the Antimony are essentially the same as I have described. (that's where I learned it ) The method involves disolving crushed Sb in Pb at temps of 700* F and lower.

Quote: "Melting temperature is 1167°F and even when melted at or above that temperature it is not easy to get a homogeneous alloy with lead." This statement, while true, is very misleading and makes me wonder if the author has really tried Mr. Fergusons recommendations.

Quote: "Lead/antimony alloy drosses considerably. As your melt reaches liquidus temperature that silvery, lumpy, oatmeal looking stuff floating on top is antimony. Skimming it off seriously depletes the alloy; it needs to be fluxed back into the melt." I've melted many tons of type alloys and the dross the author describes is very common, but it is not always present. With "foundry fresh" certified alloy it is greatly reduced and often nonexistant. I have begun to associate it with the presence of impurities such as dust and ink which provide "neucleation points" for the formation of oxides. That's just a theory of mine and until I find the time and resources to examine it I have no proof that it's true. Regardless of the reason for it's formation, it can easily be fluxed back into the melt just as he says.

I find many things in print that are at odds with my own experiences so unless I'm willing to investigate the reasons for the differences, I just have to accept the contradiction and continue to do what works for me.

Jerry

243winxb
04-04-2009, 10:20 PM
Bullet Sizes & Weights – How to Vary Them
The bullet diameters and weights presented in this list
are based on the use of Taracorp’s Lawrence Magnum
bullet alloy (2% tin, 6% antimony, 1/4% arsenic,
91.75% lead).
Bullet diameters and weights will vary considerably
depending on the lead casting alloy used. This variation
can be as much as 1/2% on the diameter, and 8% on
the weight among the most commonly used casting
alloys. For example, a .358-158 grain bullet might
show a diameter variation of .002", and a 13 grain difference
in weight.
Of the most commonly used alloys, wheel weights (.5%
tin, 4% antimony, 95% lead) will produce bullets having
the smallest diameter and heaviest weight, with
such bullets running approximately .3% smaller in
diameter and 3% heavier than bullets cast with
Taracorp's metal. Linotype will produce bullets with the
largest diameter and lightest weights. This alloy will
produce bullets approximately 1/10% larger and 3%
lighter than Taracorp. Other alloys of tin and antimony,
with antimony content above 5%, will produce bullets
with diameters and weights falling between those cast
from wheel weights and linotype.
Alloys containing little or no antimony will cast considerably
smaller than wheel weights and in some cases
will produce bullets too small for adequate sizing.
Within the limitations given above, the weight and
diameter of a cast bullet can be adjusted by varying the
alloy’s antimony content.
The size and weight of bullets of a given alloy will also
vary according to casting temperature. Higher temperatures
will result in greater shrinkage as the bullet
cools, thereby producing a slightly smaller and lighter
bullet than one cast of the same alloy at a lower temperature

armyrat1970
04-05-2009, 08:51 AM
Armyrat, There is a lot of good info on the LASC site, I refer to it often. I've read the article you cited several times before and agree with most of it, but there are a couple of significant errors in the text so, like everything else we hear or read, we have to try to separate the wheat from the chaff.

Quote from the article: " Heat treated lead, unlike steel, does NOT surface harden but achieves the same BHN all the way through." This doesn't have anything to do with Pb-Sb alloys, but I include it just to make my point. Precipitation hardening steels do indeed achieve the same hardness all the way through. Iron and mild steel can be surfaced hardened by heating in the presence of hardening agents such as Carbon or Nitrogen which results in a thin, hard surface layer.

Another quote: " Antimony can be purchased online from the “Antimony Man” but with its high melting point it is a somewhat arduous task trying to alloy it with lead. The Antimony Man supplies instructions on alloying antimony with the purchase that include the warning that the instructions must be followed precisely to be successful. In addition, antimony is extremely toxic, when handling it in a powdered form proper breathing protection and proper clean-up techniques of surrounding surfaces should be used." The instructions that Bill Ferguson supplies with the Antimony are essentially the same as I have described. (that's where I learned it ) The method involves disolving crushed Sb in Pb at temps of 700* F and lower.

Quote: "Melting temperature is 1167°F and even when melted at or above that temperature it is not easy to get a homogeneous alloy with lead." This statement, while true, is very misleading and makes me wonder if the author has really tried Mr. Fergusons recommendations.

Quote: "Lead/antimony alloy drosses considerably. As your melt reaches liquidus temperature that silvery, lumpy, oatmeal looking stuff floating on top is antimony. Skimming it off seriously depletes the alloy; it needs to be fluxed back into the melt." I've melted many tons of type alloys and the dross the author describes is very common, but it is not always present. With "foundry fresh" certified alloy it is greatly reduced and often nonexistant. I have begun to associate it with the presence of impurities such as dust and ink which provide "neucleation points" for the formation of oxides. That's just a theory of mine and until I find the time and resources to examine it I have no proof that it's true. Regardless of the reason for it's formation, it can easily be fluxed back into the melt just as he says.

I find many things in print that are at odds with my own experiences so unless I'm willing to investigate the reasons for the differences, I just have to accept the contradiction and continue to do what works for me.

Jerry

Jerry, that is one thing we do agree on. Experience in your loadings. I read a lot and take much with a grain of salt until I actually try it for my self. I feel if you find something that works best for you stick with it. But keep experimenting in case you can find something you can improve on. Nothing like proven experience in handloading from personal experience. There's so many different things involved in not only casting but just the actual steps of handloading each has to find what works best for them. It's all fun.:smile: