lead tin alloys

[Bunk Stagnerg]

Straightening out the supply shelves and I came across some 5# blocks of lead I bought years ago from a well-known bullet alloy supplier. They are marked 1-30 lead tin ratio.
There are about 20 pounds of them and my question is would they be suitable for CAS Black Powder bullets or would that be too hard?
I have a couple of DD's molds a 210 grain .452 for my revolvers and a 405 grain .457 for .45-70 Cody/Dixon shooting. In that case 100 yards would be about the maximum range they would be used. Right now I am casting all my bullets with pure lead especially balls for the front feeders. Did I find treasure?
Yr' Obt' Svt'
Bunk

[wildman1]

That would be fine for CAS. 20-1 would be a good BP ratio.  Many buy 10-1 hard cast, however most of them are shooting smokiless. For long range some of the shooters use hardcast so they can get more velocity successfully. wM1
PS Pure lead is ok for RB but your alloy  will fill out the mold much better if it has tin in it.

[Bunk Stagnerg]

thanks as soon as it gets below 100 i will melt some and run some bullets.
Bunk

[Steel Striker]

Here's a sampling of data from these sources:

Sources and References:                        
www.lasc.us/SuperHard.htm                        
www.lasc.us/CastBulletNotes.htm                        
www.castboolits.gunloads.com                        
www.rotometals.com/Bullet-Casting-Alloys-s/5.htm                        
www.midwayusa.com/browse/BrowseProducts.aspx?tabId=1&categoryId=8662&categoryString=9315***685***                     
                     
I copied a section of my spreadsheet, so this formatting didn't hold up, but you can see the alloying relationships...

Description      Composition            Uses   Hardness   Est. Hardness
Pure Lead      (100% Lead)            Minies, Round   Brinell 5   8.6
Pure Tin      (100% Tin)            Alloy   Brinell 7   -
Pure Antimony      (100% Antimony)            Alloy   Brinell 50   -
Antimonial Lead      (5% Antimony, 95% Lead)            Alloy   Brinell    13.2
Super Hard Alloy      (30% Antimony, 70% Lead)            Alloy   Brinell    36.2
40 to 1 Alloy      (2.5% Tin, 97.5% Lead)            Blackpowder   Brinell 8   9.3
30 to 1 Alloy      (3% Tin, 97% Lead)            Blackpowder   Brinell 9   9.5
25 to 1 Alloy       (4% Tin, 96% Lead)            Blackpowder   Brinell 9   9.8
20 to 1 Alloy       (5% Tin, 95% Lead)            Blackpowder   Brinell 10   10.1
Chilled Shot      (2% Antimony, 98% Lead)            Shotgun   Brinell    10.4
Magnum Shot      (5% Antimony, 95% Lead)            Shotgun   Brinell    13.2
Wheel Weight - Stick On      (0.5% Tin, 99.5% Lead)            Minies, Round   Brinell 6   8.7
Wheel Weight - Clip On      (0.5% Tin, 2% Antimony, 97.5% Lead)            Pistol, Rifle   Brinell 12   10.6
Lyman's No. 2       (5% Tin, 5% Antimony, 90% Lead)            Pistol, Rifle   Brinell 15   14.7
Hardball Alloy      (2% Tin, 6% Antimony, 92% Lead)            Pistol, Rifle   Brinell 16   14.7
Linotype Alloy      (4% Tin, 12% Antimony, 84% Lead)            Alloy   Brinell 19   20.8
Monotype Alloy      (9% Tin, 19% Antimony, 72% Lead)            Alloy   Brinell 26   28.7

[August]

I just keep adding tin until the bullets fill out the mould.  I think of the tin as important to the casting process, but not at all important to shooting at the velocities we work with.  So, you'll know when you start casting whether the amount of tin is sufficient to fill out the mould.  Have some 50/50 solder on hand in case more tin is required for getting your casting done.