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blasternank
09-30-2011, 09:29 AM
I'm a roofer and have gotten a bunch of lead pipe boots. I need to know how much tin do you mix in with it in general to make bullets. I've heard 10% but am unsure.

Thanks.

JSnover
09-30-2011, 11:03 AM
I think the reference alloy for Lee molds is 10% tin but realistically, it sounds like most folks don't need more than 5%: Just enough to get a good fill.

fatelk
09-30-2011, 11:26 AM
I've often wondered why Lee calls for 10%. It seems like an incredible waste of tin to me. I think even less than 5% is normally enough. JSnover is absolutely correct about just enough for fillout.

I wonder if Lee has some reason for saying 10%; never made sense to me.

docone31
09-30-2011, 12:18 PM
I use mostly roof boots.
I use no tin, I use heat on the mold, and in the mix. I am happy so far.

hiram
09-30-2011, 12:23 PM
I read somewhere, perhaps the Lyman casting manual, that lead will mix with no more than 2% tin. Think about it, people cast with ww which has less than 2% tin and get good boolits. If I am correct, then 20:1 is an excessive use of tin. 20:1 is 5% tin. 50:1 is 2% tin.

garym1a2
09-30-2011, 01:13 PM
Lyman #5 is 90pd/5sn/sb
Good all around alloy.
You precent depends what you shoot in and how fast.
High speed rifle needs more sb.
45acp needs less tin and sb.

JSnover
09-30-2011, 01:21 PM
I know some babbit metal is way more than 2% tin. I try to go for 2-3%

a.squibload
09-30-2011, 01:26 PM
Before reading on this site I never added tin,
now I get better boolits using a little tin, 1% or less.
I ran a batch of ½ WWs and ½ soft lead with a few ounces of pewter,
maybe 10 lbs total.
Best looking boolits I ever cast, and shot well too...:D

pdawg_shooter
09-30-2011, 01:34 PM
I shoot for 2% to 3% when I need it for fill out. Never have had to add any to WWs.

cbrick
10-01-2011, 01:05 AM
I read somewhere, perhaps the Lyman casting manual, that lead will mix with no more than 2% tin.

I've never heard that before, don't think the metals industry has either.

What it is that you don't want to do is use a higher percentage of tin (Sn) than the percentage of antimony (Sb) in a Pb/Sb alloy. Wheel weights have roughly 2% Sb and about .5% Sn so 1.5% to 2% Sn is all that's needed and more woud be a waste.

The OP wants to know how much Sn to add to pure or nearly pure Pb and as was already asked, what are you shooting? Seems someone told him 10% Sn, that's fine for BP but for smokeless would be way too much. For smokeless rifle loads a little Sb would be a benefit with about 2% Sn max.

Rick

Gtek
10-01-2011, 10:50 AM
You will need to experiment with what you are casting for. Boolit size, mold type, pot temp, and boolit diameter, dump angle, ladle or bottom are all variables in your quest. Keep a log- trust me it is worth it! I would start at 2% and remain constant on process, throw twenty to make sure mold up to par and keep in line to confirm. If fill out is what your chasing I assume, on with the hunt. If not happy with results, cool pot and back in they go. Increase tin % a bump and go again. Sorry, this game has nothing in stone! But I do know the more you do the better you get. Be Safe-Gtek

Suo Gan
10-01-2011, 11:19 AM
I'm a roofer and have gotten a bunch of lead pipe boots. I need to know how much tin do you mix in with it in general to make bullets. I've heard 10% but am unsure.

Thanks.

Watcha shootin? Some of the old standbys are 20-1, 30-1. or even 40-1.

For low pressure shooting I like to mix pure lead and split it 50/50 with wheel weights. I add about 2 percent tin to this alloy mix for castability. That means a 20 pound pot of lead will get six or seven ounces of tin.

montana_charlie
10-01-2011, 12:46 PM
An extremely good alloy for sub-1500 fps work is 97/1.5/1.5
It will test at 8.2 BHN right after casting, but will stabilize at 9.8 BHN after only 18 hours.

You can do the math to create this alloy from anything that has antimony in it.
But those who are using it call it the 'three - seven' alloy ... because it is three parts Lyman #2 and seven parts pure lead.

CM

Sonnypie
10-01-2011, 08:40 PM
By weight:
90 pounds of lead.
5 pounds antimony.
5 pounds of tin.

Yeild is 100 pounds of alloy and it is also called Lyman #2 formula. AKA: 90/5/5
Which is one ages old standard for casting.

You can break that down easily for lesser amounts:
45 # Pb
2.5# Antimony (Sb)
2.5# Tin (Sn)
Yeild 50 pounds Alloy

22.5# Pb
1.25# Sb
1.25# Sn
25 pounds of alloy

I'm real Scientific about mine....

Tin is doggone expensive to add. A 1 pound roll of lead-free solder cost me neigh $25.
Rotometals sells tin at $17-18 a pound.
I found that I can get Magnum shot locally for 1.40 a pound. ($35 for a 25# bag.)
It runs 4-6% Antimony Sb.
I would have to add $21.25 of RM Tin (1.25) to get close to Lyman #2.

This is where my "pure" science comes in:
To a 20# pot of that shot melted down (for casting 45 Cal boolits), I add about 24" of 1/8"dia Lead-Free solder. My BHN initially is (same day as cast) 11.8 for Air Cooled, or 12.1 for Water Dropped.
Either way, when the powder goes pow, the lead flies. :veryconfu
The formula is.... uhh.... ummm.... awe... :confused: :violin:

Rather than mix my own Lyman #2 for my 30 cal boolits, I buy Rotometals formula.

So far, my Scientific Formulation has punched quite a few holes in paper, and rung the long range steel at the range.
Most of your boolits are on a one way trip anyway. So the fuss and bother does not seem to be worth losing sleep over. [smilie=6:

Scroll down this page and do not miss the bottom. There is your answer.
"Basic Rules for Harding Lead-

For every 1% additional tin, Brinell hardness increases 0.3.
For every 1% additional antimony, Brinell hardness increases 0.9.
For a simple equation,
Brinell = 8.60 + ( 0.29 * Tin ) + ( 0.92 * Antimony )"

From Rotometals (http://www.rotometals.com/Bullet-Casting-Alloys-s/5.htm)

Have fun, not worries. :drinks:

USSR
10-01-2011, 08:46 PM
My standard handgun alloy is 25-1 (4% tin).

Don

ColColt
10-01-2011, 08:55 PM
For years I just used 50/50 lead to Linotype for an approximate Lyman #2(bhn 15). You can mix more lead to drop the hardness. I now use (when I can get it) ww's plus about 2% tin and find it excellent for all my pistols.

bumpo628
10-01-2011, 09:37 PM
This is where my "pure" science comes in:
To a 20# pot of that shot melted down (for casting 45 Cal boolits), I add about 24" of 1/8"dia Lead-Free solder. My BHN initially is (same day as cast) 11.8 for Air Cooled, or 12.1 for Water Dropped.
Either way, when the powder goes pow, the lead flies.
The formula is....

I'm on it...
The 24" of solder should weigh about 1-1/4 oz.
20 lbs magnum shot + 1.25 oz lead free solder = alloy with @ 0.35% tin, 6% antimony

Sonnypie
10-01-2011, 09:55 PM
:lol:
Thank You, Bimpo! :lol:
:lol:

All I know is it seems to work well in the mold, and the 1911A1.

larryy
10-02-2011, 11:05 PM
A great site that explains different alloys for different speeds and is a veritable bible for casters is the free online book "From Ingot To Target" by Glen Fryxell. It has more good advice then I have gotten from "friends" over the last 40 years. There is also a good chart from this site [alloy05.xls] for calculating amounts to mix for different ratios that is a godsend for the mathmatically challenged like me.

cbrick
10-02-2011, 11:18 PM
Welcome to Castboolits larryy,

The book you reference is a stickie in the "Classics & Stickies" section and the "Cast Boolits" forums of this site. Here is the link to the pdf version.

From Ingot To Target (http://www.lasc.us/Fryxell_Book_textonly2.pdf)

Rick