What do I need tin for again?

[Bnt55]

Is mold fill out the only reason to add tin to my lead when casting?? I'm all about hunting for pewter pieces in dusty old basements, but before I get myself covered in cobwebs, is this really necessary or is it just another step down the reloading rabbit hole?

[zarrinvz24]

For the most part yes. Elmer stated in sixguns that he used 1:16 for magnum loads, and 1:20 for everything else. Antimony and Copper are good for making boolits hard, but hard isn't neccesarily what we are after. Lead/tin alloy offers a tough to beat combination. If Antimony weren't so commonly available in WW alloy, I'd bet we wouldn't really use much of it either.

[kbstenberg]

+1 ^^^
Reason 1 mold fill out better consistancy
Reason2 better bullet performance on game animals.

[Sasquatch-1]

Think of it like dish soap on dirty water where it pushes the dirt away. The tin breaks the surface tension and allows for good fill out and hopefully, no voids in the bullet. Anything over 2% tin is wasting tin. I only add when having poor fill out.

[toallmy]

Go on down the rabbit hole , you will eventually do it .
Tin is magical

[OS OK]

FROM THIS ARTICLE.... http://www.lasc.us/FryxellCommentsCBAlloys.htm

There is a world of knowledge over there if you guys will take the time to read it...

(Historically, tin was used to harden bullet alloys because it was widely available, it was easily mixed with molten lead, and it improved the "cast-ability" of the alloy considerably (tin lowers the surface tension of the molten alloy and allows it to fill out the mould more completely). However, in recent years tin has gotten to be rather expensive. In addition, it's really not all that effective at hardening lead alloys. Antimony hardens lead alloys much more effectively than does tin, and is cheaper to boot, so antimony is the primary hardening component used in lead alloys today. In addition, antimony allows the alloy to be hardened via heat treatment, something the chemistry of tin doesn't allow (and arsenic is even better for heat treating than is antimony). Antimony has limited solubility in molten lead, but tin enhances its solubility through the formation of an inter-metallic SnSb compound, which is more soluble.

Thus each component contributes something different to the whole: tin provides cast-ability (2% is really all that's needed) and "mix-ability", antimony provides hardness and the ability to harden through heat treatment, and a small amount (0.05-0.5%) of arsenic (which in and of itself doesn't harden the alloy appreciably) significantly enhances the heat treat-ability of the mix.)

[Soundguy]

as said.. tin helps fill out.. surface tension.. and a little hardness. I do lots of 10:1 shooting...and 20-1 etc.

[gwpercle]

Sixgun Cartridges & Loads , Elmer Keith , 1936 .
Chapter 4 - Bullet Casting - Tin / Lead - bullet alloy - 1 part Tin to _ parts Lead

1 / 20 - "For most revolver cartridges including all light and normal pressure loads there is no use having the boolits harder than 1 part tin to 20 parts lead ."

1 / 16 - "For heavy loads a 1 in 16 is hard enough for velocities above 1000 fps." ( In 1936 he was using 1 / 15 but later changed to 1 / 16 )
Actually 1 / 15 ... or ... 1 / 16 would probly work fine .

1 / 10 - "For auto-loading pistol "( and 30 cal. rifle)

Tin / lead alloy worked for Elmer ... I suspect he didn't have a ready access to clip on wheel weights .
Lead and tin would have been accessible and today with wheel weights going away ...might be what we need to start looking at .
I bought this book for this info on casting boolits without wheel weights , if you want the reprint of this manual it's (is or was) $10.00 at Amazon w/ free shipping .

Pewter isn't the only source of tin ... I use 50-50 bar solder to get mine .

Gary

[Bnt55]

Thanks for the info, I have a mix of soft and COWW available. Looks like I will see if I can get my hands on some tin for the soft stuff.

[RogerDat]

Tin also shifts the melting point lower. Increases the ductile properties of the bullet. Meaning bullet can expand more before it breaks. Especially useful for hollow points or a flat nosed hunting bullet.

Pewter usually adds some copper which makes the metal "tougher" rather than harder. Only a small amount of Cu but it can improve expansion properties or help a bullet stay together on impact. Say hitting large bone in a game animal the bullet stays together it continues on with more momentum than it would if it broke apart. Copper alloys with tin, pewter is high tin and thus can have a copper alloyed into it.

Pewter also doesn't dilute the antimony to add tin the way solder would. Solder being lead/tin alloy is diluting the COWW alloy antimony content. Pewter is usually a higher percentage of antimony than COWW's so doesn't reduce the percentage when adding tin using pewter.

Digging around those basements don't forget to keep an eye out for rolls of solder. Shows up cheap in garage and estate sales sometimes. I collect all summer then melt in big batch once I have enough to make it worth having tested. End up with a lot of 23% or 40% solder that way.

[JoeJames]

I have mostly been casting for 32S&W Long, 38 Special, and 44 Special. I am not much for high velocity either. So I did the pure lead and tin mix at first, and then got a 6 gallon bucket of wheel weights. I may add a few inches of tin out of a roll of 95% tin - lead free solder now and then to improve casting a bit, but the wheel weights are my main thing now.

[gwpercle]

I have mostly been casting for 32S&W Long, 38 Special, and 44 Special. I am not much for high velocity either. So I did the pure lead and tin mix at first, and then got a 6 gallon bucket of wheel weights. I may add a few inches of tin out of a roll of 95% tin - lead free solder now and then to improve casting a bit, but the wheel weights are my main thing now.

My unlimited free supply of wheel weights recently retired from the tire shop business , I had it good for about 50 years and cast everything of straight wheel weight metal , the free wheel weight supply is gone So ...now the wheel weights I have get mixed 50-50 with soft scrap lead or range scrap and the 50-50 mix works extremely well in both revolver , auto-pistol and 30 cal rifle . Maybe better than straight wheel weights .
If you need / want to streatch your wheel weight supply , give it a try .
Gary

[Scrounge]

For the most part yes. Elmer stated in sixguns that he used 1:16 for magnum loads, and 1:20 for everything else. Antimony and Copper are good for making boolits hard, but hard isn't neccesarily what we are after. Lead/tin alloy offers a tough to beat combination. If Antimony weren't so commonly available in WW alloy, I'd bet we wouldn't really use much of it either.

Antimony is a weird metal. When it cools, it expands a bit, unlike most stuff. That and a bit of hardness that it adds to lead is why it's used. It helps fill the mold properly, and hardens the boolits. Sometimes you need that. The tin makes the melt flow better, so it also helps with filling the mold. You don't need much of either one, but unless you want dead soft boolits, you need some of each.

[Soundguy]

Trace Amounts of Arsenic and copper fantastic 2

[Beagle333]

I like 2.5%, but I cast mostly HPs. I use pewter most of the time. I buy all my pewter here on the S&S forum. There's none to be had locally.

[243winxb]

Tin lowers the melt temperature. Better flow. Same as turning up the heat.

[William Yanda]

From my reading of the Fryxell/LASC article, a three metal blend of lead, tin and antimony makes the alloy "tougher" without becoming brittle. This is able to resist slipping as it engages the rifling and not shatter when it hits the target. Not shattering is irrelevant for paper but invaluable for hunting. Being soft enough to obdurate to fill the bore, but tough enough to engage the rifling positively is a definite plus for accuracy.
So, why are you shooting, hunting or target? What are you shooting, rifle or pistol? What velocity are you shooting? All of those answers will determine the correct response to your original question.

[William Yanda]

" it continues on with more momentum than it would if it broke apart" Rogerdat

From a physics standpoint, the momentum of the individual pieces will equal the momentum of the original object. If momentum were lost, where would it go?

[zarrinvz24]

" it continues on with more momentum than it would if it broke apart" Rogerdat

From a physics standpoint, the momentum of the individual pieces will equal the momentum of the original object. If momentum were lost, where would it go?

The momentum is expended faster over a larger area than it would be if it remained in one piece, and retains momentum over a smaller area.

[fredj338]

I almost never add tin. I have added lino to pure, which has tin, but I never have issue with fill-out with 9mm & up bullets.