Lead alloy recipe's

[BobinIL]

Hi all

I am new to the board. I have been casting for several years with straight wheelweights. I only use the cast bullets for cowboy matches. I have recently aquired a large abount of pure lead and some Linotype. What ratio of mix should I use to get close to the composition of wheelweights??

[runfiverun]

try 3 parts pure to 1 part lino.
that wil be close to ww's, you could even mix that 1-1 with ww's and add some more pure.
and a smidge of tin if needed for fill-out.
ww hardness isn't fully needed for c- boy poof loads.

use what you got the most of, you can run near pure up to 750-800 with good lube.
this is what swaged boolits are.

[MakeMineA10mm]

I agree with runfiverun. For cowboy loads, I mix up my standard "soft" alloy:

38-1/4 lbs WW
34-7/8 lbs Pure Lead
1-7/8 lbs 95/5 “lead-free” bar solder (or straight tin)

This gives me an alloy of approx: 96% Lead, 2.5% Tin, 1.5% Antimony



If you want a harder alloy for 9mms, 357s, 44 Magnums and such, you could try my "medium" alloy:

72-1/2 lbs WW
1-2/3 lbs 95/5 “lead-free” bar solder (or straight tin)
3/4 lbs Linotype

This gives me an alloy of approx: 94.5% Lead, 2.5% Tin, 3.0% Antimony

[grumpy one]

I agree with runfiverun. For cowboy loads, I mix up my standard "soft" alloy:

38-1/4 lbs WW
34-7/8 lbs Pure Lead
1-7/8 lbs 95/5 “lead-free” bar solder (or straight tin)

This gives me an alloy of approx: 96% Lead, 2.5% Tin, 1.5% Antimony


I disagree with the use of more tin than antimony in any cast bullet alloy. Dennis Marshall, on page 29 of the RCBS Cast Bullet Manual, says it will produce bullets with soft spots. If you look at the sticky on "Toughness of Lead-Tin-Antimony Alloys" on this board you will see the reason for my own disagreement with the practice: it just wastes tin. On the other hand the use of equal amounts of tin and antimony gives important advantages in ductility and toughness. It also provides excellent castability, and really shiny bullets.

In practice we usually aren't too sure of the exact composition of our WW, so aiming for equal amounts of tin and antimony will sometimes result in a _small_ excess of tin. I have not seen any detriment to castability, ductility or toughness from this.

[miestro_jerry]

I use 90% Lead, 5% Tin Or Lead Free Solder and 5% Antimony, it's called Lyman #2. Some times I will make an alloy that 90% WWs and 10% Tin. When I can get it, I use Lino for the very high speed bullets with out any further alloying.

Jerry

[Tom Herman]

I agree with runfiverun. For cowboy loads, I mix up my standard "soft" alloy:

38-1/4 lbs WW
34-7/8 lbs Pure Lead
1-7/8 lbs 95/5 “lead-free” bar solder (or straight tin)

This gives me an alloy of approx: 96% Lead, 2.5% Tin, 1.5% Antimony

Excellent alloy! I make one very close to this: Ten pounds WW, ten pounds scrap lead, and 6.4 ounces lead free solder.
I have almost zero leading with this in .45 LC, .44 SPL, and .455 Webley. Except for the slower Webley, my speeds run about 750 FPS. Lube is SPG.

Happy Shootin'! -Tom

[runfiverun]

i also favor a balanced mix but always leave the tin on the low side.
with ww's i use 2% tin you will be told it is too much but i donot think so.
especially if you want to water drop.
the equal mix provides for a stronger SbSn chain.
if you have a longer sn [tin] chain it will cause you probles because sn likes sb more than pb
and the excess is torn away from the snsb chain in cooling leaving spots of free sn
causing hard spots of sn with soft spots around them where there is no bonding because of the cooling rate difference..
or something like that.............it can be explained backwards but that is the way i think of it.
anyway either all tin or more antimony then tin, or equal amounts of both.

[GabbyM]

Lino is supposed to be 4/12 or 4% tin , 12% antimony when fresh.
So cutting it with three parts pure lead would give 1.3/4 alloy. Whel wieghts are roughly 1/2% tin 4% antimony so the 3:1 mix would be like WW with 1% tin added. Your resulting BHN would be around 13 to 14. Depending on how pure your pure lead was.

With a BHN of 13 and using the formula (1440 x BHN) you have a minimum pressure to obturation of 18,720 psi. Cowboy loads are probably under that level. Since that's above the max pressure on 38 Special loads. Lino being expensive I'd dilute it more for Cowboy loads. Some mix 50/50 WW/lead for low pressure loads. For 750fps loads a 6 or 7 to 1 would work. May need a little tin to fill out some molds. It's sort of a shame to dilute lino that much. But if that's what you have then use it. Linotype isn't rare or hard to find. You can still buy it fresh from the foundry. Last I looked it wasn't even a special order alloy. Of course that's not the best lead. As we all know the best lead is free lead. I've never asked for a quote on new lino. But I'll bet it's close to the $1.50 they get for it as dubious scrap on ebay. My last load of 2/6 was $1.30 per lb. FOB and the price of lead has dropped a few cents since then.

[MakeMineA10mm]

I disagree with the use of more tin than antimony in any cast bullet alloy. Dennis Marshall, on page 29 of the RCBS Cast Bullet Manual, says it will produce bullets with soft spots. If you look at the sticky on "Toughness of Lead-Tin-Antimony Alloys" on this board you will see the reason for my own disagreement with the practice: it just wastes tin. On the other hand the use of equal amounts of tin and antimony gives important advantages in ductility and toughness. It also provides excellent castability, and really shiny bullets.

In practice we usually aren't too sure of the exact composition of our WW, so aiming for equal amounts of tin and antimony will sometimes result in a _small_ excess of tin. I have not seen any detriment to castability, ductility or toughness from this.

Hiya grumpyone! (Are you trying to live up to your name? :-D )

I'm not familiar with the RCBS manual. Have the Lymans and Paul Moore's book on commercial casting. I'm interested in what you say and will look up those references you give and do some reading.

I do have a couple conflicting thoughts with what you're saying:
- I think the percentages I'm aiming at with my soft alloy are so low that variations in the hardness are not a huge factor. (We're talking an alloy that's mostly pure lead already - pushing it hard will do bad things, whether the tin/antimony causes soft spots or not... My soft alloy is about 191 parts lead, 5 parts tin, 3 parts antimony, and 1 part [or less] trace elements.)
- I question the argument about high tin values, in light of the many folks who shoot tin-lead (only) mixtures at very high percentages (like 1-20 tin-lead), but maybe the addition of antimony changes the chemistry - I need to read your sources.
- The Moore book indicates that more than 2.5% tin adds no value to a lead alloy insofar as hardening is concerned. (He also asserts that good fill-out can be achieved at a lower level of tin than that. This is the basis for the Taracorp Magnum alloy that commercial casters use, consisting of 2% tin - It's a good compromise between cost, castability, and hardening value.)
- The Lyman book also indicates that above a certain point, tin's primary value is to cause good fill-out of the boolits in the mould vs. hardening. (Basically, what I'm doing is creating a soft alloy with minimal antimony, and bumping up the tin to cause good fill-out more than hardening, though I'll take what hardening it does, just so long as it is not too much...)

In all the casting and shooting of cast boolits I've done, I agree with these principles and haven't seen anything to contra-indicate them. Of course, all but a small portion of my casting has been for pistol calibers.

I fully expect that with the more stringent accuracy requirements, combined with higher pressures, heat and velocity, the principle(s) you're talking about may very well become quite important when casting rifle boolits. Perhaps that was what you were getting at, but, to answer the original poster's questions, I felt he was primarily talking pistol calibers, due to the reference to cowboy shooting...

Either way, happy shooting to us all! :drinks:

[MakeMineA10mm]

Excellent alloy! I make one very close to this: Ten pounds WW, ten pounds scrap lead, and 6.4 ounces lead free solder.
I have almost zero leading with this in .45 LC, .44 SPL, and .455 Webley. Except for the slower Webley, my speeds run about 750 FPS. Lube is SPG.

Happy Shootin'! -Tom

Hey Tom! Yes, it works really well. No leading, good obturation, and it even expands some! (This is also my Hollow-Point Boolit Mould alloy.) Oh yeah, and it's pretty cheap! (The tin is about the only thing that costs much for me.)

I commercially cast for a couple years and used both alloys I made up and commercial alloy from foundry, and I agree with all those here who declare the commercial alloy too darn hard. (I had quite a custom business making boolits to softer alloys for people.)

You should try a smaller-sized version of my medium alloy. It basically cuts in half the antimony level of the commercial "magnum" alloy, with a scosh more tin. It works well in everything (pistol-calibers, that is), and is my standard alloy (except for cowboy/black powder/hollow points). I also like it because it makes best use of my large stockpile of WW material, and slowly sips at the short piles of tin and linotype I own... :mrgreen:

[buck1]

Sell it ,or trade it . WWs are much easier to get than pure lead or lino. My $0.02

[grumpy one]

Hiya grumpyone! (Are you trying to live up to your name? :-D )


I do have a couple conflicting thoughts with what you're saying:
- I think the percentages I'm aiming at with my soft alloy are so low that variations in the hardness are not a huge factor.


- I question the argument about high tin values, in light of the many folks who shoot tin-lead (only) mixtures at very high percentages (like 1-20 tin-lead), but maybe the addition of antimony changes the chemistry - I need to read your sources.

- The Moore book indicates that more than 2.5% tin adds no value to a lead alloy insofar as hardening is concerned. (He also asserts that good fill-out can be achieved at a lower level of tin than that. This is the basis for the Taracorp Magnum alloy that commercial casters use, consisting of 2% tin - It's a good compromise between cost, castability, and hardening value.)
- The Lyman book also indicates that above a certain point, tin's primary value is to cause good fill-out of the boolits in the mould vs. hardening. (Basically, what I'm doing is creating a soft alloy with minimal antimony, and bumping up the tin to cause good fill-out more than hardening, though I'll take what hardening it does, just so long as it is not too much...)



Tin is not usually used to improve hardness, except in tin-lead alloys which are not what I was talking about and are only competitive with lead-tin-antimony alloys in the hardness range below say 10-12 BHN. Tin is used with antimony for two purposes: to improve the castability of lead-antimony alloys; and to combine with the antimony to form the compound SbSn which has superior toughness and ductility compared with crystals of Sb alone.

Taracorp Magnum alloy (2/6, sometimes called Electrotype in Australia and I think in Britain, because it has been used as a typecasting metal) is a poor bullet casting alloy because it has more than the optimum amount of antimony (about 4%), which makes it relatively brittle without any compensating advantages.

Generally, alloys of more than about 10 BHN, up to 24 BHN, have the best combination of toughness and ductility if they are pseudo-binary (i.e. they have equal amounts of tin and antimony). I haven't tested these with lower alloying than 2/2, but heat-treated 2/2 seemed likely to be a very impressive alloy for, say, the upper end of the pistol range. I'd expect something like 1.5/1.5 to be excellent for "normal" magnum revolver loads, and substantially lower amounts of alloying would be best for lower pressure revolver loads. I make no comment on autoloader loads because performance on the feedramp becomes critically important, especially in defensive situations, and that is a different requirement compared with focusing on impact performance.

My experimental results on these issues are in the sticky, "Toughness of Lead-Tin-Antimony Alloys".

[randyrat]

For cowboy loads just go 50-50 = WWs/ pure . I doubt you'll have any problems. I use this in my light 45 acp loads. I'm finding it's easier to get soft lead now than WWs. I would conserve your WWs or Lynotype as much as possible. Don't use tin unless absolutely needed. Save you alloys for hunting bullets and higher velocities if needed. As far as recipes- good luck figuring that out...Go by weight- Try to match your bullets by wieght, then you'll be very close to the recipe you want. Too many of my alloys vary so much i can't pencil out a recipe.

[MakeMineA10mm]

Tin is not usually used to improve hardness, except in tin-lead alloys which are not what I was talking about and are only competitive with lead-tin-antimony alloys in the hardness range below say 10-12 BHN. Tin is used with antimony for two purposes: to improve the castability of lead-antimony alloys; and to combine with the antimony to form the compound SbSn which has superior toughness and ductility compared with crystals of Sb alone.



Just as a follow-up... (I'm posting here rather than the other thread, because it seems more germane to this discussion.)

With a tertiary alloy (made up of the three elements, tin, lead, and antimony), it seems to me most of your suggestions/points have been restricted to the topic of utilizing tin and antimony in equal amounts in order to create SbSn.

It is well known (and I think you mentioned it somewhere - or maybe I read it in Dennis Marshall's article) that plain lead doesn't cast very well, and the addition of tin assists in fill-out and sharp corners, etc.

It's also mentioned that tin up to a certain point assists with this fill-out. (Paul Moore whom I mentioned earlier, says that it's cost vs. benefit tops out at somewhere around 2-3%.)

I've also read (either by you or Marshall) that tin and antimony will combine to form SbSn, and that if either element has more presense than the other, that metal will NOT go into the SbSn suspension and merely exist in the alloy, supporting it's own properties, and not giving the combination properties of SbSn.

We've also agreed that most alloys are too hard for pistol boolits. So, that leads to my question of:

If I want to cast some soft pistol bullets, but utilize my commonly-available alloy, such as wheelweights, and get decent fill-out, by adding tin, what is the harm in getting the tin up to a level that's slightly above the percentage of the antimony in the mix.

In other words, let's say I mix 1 part WW with 3 parts pure lead and add in 2% tin for castability. The resulting mix would be somewhere around 2% tin, 1% antimony, and 96.5% lead (remaining quantity being trace elements from the WW). The way I understand things, the 1% antimony and 1% of the tin will combine to form SbSn (2% of the mix we just made), and 1% of the tin will remaining in the alloy NOT as a part of the SbSn compound. Why would that extra 1% of tin be bad? I would think that it would help make the alloy fill out the moulds better and overall would not be problematic to the mix. Maybe even provide a little hardness, since we're talking such a soft alloy mix in this case. Where am I wrong?

(I recognize that you cited Dennis Marshall stating that excessive tin would cause soft spots, but I didn't catch that when I read the article. I also wonder if Dennis and you are advocating that the best possible cast bullet alloys are only those which convert the vast marjority of their tin-antimony into the compounded SbSn?)

[ForneyRider]

For those skimming the WW to remove the Zinc, aren't you removing the Antimony as well?

[felix]

Yes, but only a small amount of the total, assuming the base metal in the pot was already prepared well. The rule is to never empty the pot during the pouring phase. ... felix

[runfiverun]

10 mm
your last paragraph i totally agree with 100 %.
the other [i believe] felix I and grumpy one discussed in this ,and the other thread.
if you believe or know something different i would be interested in hearing it.
maybe excess tin with such a small amount of antimony is not a problem.
as the chain isnot long enough te tear and the tin will bind instead of tearing
due to the excess length of the sn chain?

[grumpy one]

...
If I want to cast some soft pistol bullets, but utilize my commonly-available alloy, such as wheelweights, and get decent fill-out, by adding tin, what is the harm in getting the tin up to a level that's slightly above the percentage of the antimony in the mix.

In other words, let's say I mix 1 part WW with 3 parts pure lead and add in 2% tin for castability. The resulting mix would be somewhere around 2% tin, 1% antimony, and 96.5% lead (remaining quantity being trace elements from the WW). The way I understand things, the 1% antimony and 1% of the tin will combine to form SbSn (2% of the mix we just made), and 1% of the tin will remaining in the alloy NOT as a part of the SbSn compound. Why would that extra 1% of tin be bad? I would think that it would help make the alloy fill out the moulds better and overall would not be problematic to the mix. Maybe even provide a little hardness, since we're talking such a soft alloy mix in this case. Where am I wrong?

(I recognize that you cited Dennis Marshall stating that excessive tin would cause soft spots, but I didn't catch that when I read the article. I also wonder if Dennis and you are advocating that the best possible cast bullet alloys are only those which convert the vast marjority of their tin-antimony into the compounded SbSn?)

First, the Dennis Marshall article I referred to is the one in the RCBS Cast Bullet Manual, not the one in the Lyman Cast Bullet Handbook. They are different articles - the RCBS one is specifically about heat treatment.

The topic of what happens to excess tin when it exceeds the antimony percentage in a ternary alloy of lead-tin-antimony is a mystery to me at this point. I haven't found a useful reference on it. I am not prepared either to accept or reject Marshall's statements in the RCBS book without having some grounding in the relevant theory. Hence I can't answer your question on this. You need either to believe Marshall, or find a reference to serious literature. Personally I think Marshall's statements are most likely correct - he's no beginner at this stuff - but I won't accept his position as valid theory without an explanation.

With regard to your last paragraph, I have found that pseudo-binary alloys (those with equal tin and antimony) are 26-29% tougher than typical low-tin alloys, and are more ductile as well. The accompanying disadvantage is that they have lower hardenability, so if you need more than say 24 BHN, you have to reduce the tin content to be able to get it. Hence, so long as you can achieve your required hardness, my current position is that pseudo-binary alloys give higher performance than low tin alloys. The best alloy, by my current level of understanding, is - for rifles and magnum revolvers - lead with the lowest (but equal) amounts of tin and antimony added that will achieve your toughness and castability needs. For standard revolvers I believe lead with a smallest viable amount of tin added would be best.

Note that what I have said here is simplistic. Felix has ventured into far more exotic options, and has found some excellent results. If I live long enough, perhaps I'll eventually find some explanations that I can understand, for what he has made to work. If not, most people will be satisfied by the fact that it does work.

[MakeMineA10mm]

OK, makes sense to me.

For the record, I'm not a chemist or a scientist, and beyond some college biology/zoology, my other experience with science is toxicology reports and autopsies. This means I recognize proper method and have some grounding in basic science, but I'm NO chemist! :mrgreen: Therefore, some of what is written (here and in the Marshall article) is well over my head, although I get the gist of it. (I just don't thoroughly understand it.)

As far as my main question, I think I'm good. It sounds to me a lot like you guys are studying this question for hardness and higher velocity stuff. 95% of my cast boolit shooting is pistol (or to be more precise - pistol CALIBERS - sometimes shot in carbines), where the requirements are less demanding as far as hardness goes, and heat-treating is rarely needed.

My alloys are fairly soft. (My medium-hard alloy is WW + 1-2% tin, which is close to a binary alloy, depending on the variability of the make-up of the WWs in question.) They serve me well in my pistol and pistol-caliber-carbine shooting. That's why I got a little concerned and really thought about my alloys when grumpy-one pointed out that I might be creating soft spots or other problems with my soft alloy...

We need to talk to Ken about making an icon or something for our profiles that indicates if we are rifle, shotgun, pistol, or muzzle-loader cast boolit guys. That would help clarify when we're talking about alloys, lubes, etc., whether we're making broad comments, or specific ones to a particular aspect of casting... :drinks: