here I go again, trying to figure out a mystery alloy.

[corey012778]

a month or so ago, I posted something about buying a ingot of a mystery alloy.

clues I have on it is.
melts around 450degrees
cast boolits 100grs lighter then lead at 6.7bhn (lee 501-440 test mold) and .003 larger
takes a long time to cool
new clue: bhn of 33

what do I have?

[badbob454]

foundry type?

[runfiverun]

probably mono.
lino is the same,but 22 bhn.
mono has more tin and antimony and is harder,but has about the same melt point.
20% lighter than lead shows about 20% something other than lead in the mix.

[badbob454]

http://www.lasc.us/Kelter_Cast_Bullet_Alloys2.pdf
see page 5 prob foundrytype hard stuff
I'm far from an expert, so I tend to refer to bumpo's alloy calculator to get an idea of ratios:

Linotype: 4.00% Sn - 12.00% Sb - 84.0% Pb = 19 Bhn

Monotype: 9.00% Sn - 19.00% Sb - 72.0% Pb = 26 Bhn

Foundrytype: 15.00% Sn - 23.00% Sb - 62.0% Pb = 30 Bhn