I just got back into casting last year and I've been trying to come up with a good all around alloy mostly for handguns up to around 1200 fps.

I have several hundred pounds of monotype I bought from an old printshop. I had a scrap yard xray gun some of it and it has 74.53% lead, 17.74% Sn and 7.73% Sb . It's hard stuff so I've been adding one pound of it for every 4 pounds of wheel weight lead. Seems to work so far but I have no idea how hard it really is and what alloy blend it would be similar too.

What would your guess be on this blend? Do you recommend I do it differently? I've hit some bullets with a hammer after cast and they start to flatten out some but don't fracture or break.

Thanks,
Bb

If I did my math correctly, based on what alloy estimates online that show 95% lead, 0.5 tin, and 4 of Sb, my alloy after blending should be approximately 91% lead, 2% tin, 6.75% antimony and some trace arsenic and other ww inputs.

So I'm basically casting 91Pb, 6.75 SB, and 2 Sn. Whatever it is it seems to work in my limited testing and seems to be medium hardness air dropped yet will not fracture.

Is there a better blend I could try? I have maybe 1000 pounds of this monotype left. I actually have more of it than I do ww lead.

Bb

I've used pencil hardness testing on range salvage lead when I cast ingots to see what I have. Done properly it is accurate and inexpensive. It will give you a good idea of what you have.
Pencil hardness testing lead.

Have never pursued the pencil test, but do have a Lee hardness tester. It is quiet simple and accurate. Bought mine when they were $30-35, but I see these days they are $70 from Amazon and $100 from Lee.

Simple test? Shoot it and if it works move on down the road.

Might find some insights that simplify thing on this website. http://www.lasc.us/CastBulletNotes.htm

Looking at notes you will see hardness values for various alloys, to include monotype. Hardness is reasonably linear as an alloy ratio.

Alloy BHN
Lead 5
WW (stick on) 6
Tin 7
1 to 40 tin lead 8
1 to 30 tin lead 9
1 to 20 tin lead 10
1 to 10 tin lead 11
WW (clip on) 12
Lead Shot* 13
Lyman # 2 15
Water quenched WW 18
Linotype 18 - 19
Monotype 25 - 27
Oven heat treated WW 30 - 32
Antimony 50