1 CAST BULLETS FOR BEGINNER AND EXPERT SECOND ... - Home

The addition of more than 10% tin to lead does not increase the hardness of the alloy
much. Most of the hardness from tin is obtained with the first 5%.
The addition of antimony does increase hardness in proportion.
There is some arsenic in most lead alloys. Arsenic seems to be important in the heattreating
of bullets. Arsenic is essential to increasing hardness by heat treating and quenching as it
provides the needed “interlocking of the lead and antimony crystalline structures” – ask a
metallurgist for a better explanation..
Wheelweights are cheap and easy to find and work well for casting most pistol bullets
and rifle bullets.
If harder bullets are required, linotype can be used. Linotype metal is easy to find, is
about $1 per pound in 2006, and is hard enough for rifle bullets up to a reported 2300 fps and
sometime more.
Heat-treating or "quenching" bullets cast of wheelweights will increase their hardness.
Heat-treating cast bullets to increase hardness is not necessary for most shooting, and is best left
to the more advanced caster and reloader. For an excellent explanation of these processes, see
"Bullet Quenching" and "Heat Treating Cast Lead Bullets".
This graph is from "Type Metal Alloys" By Frances D. Weaver, B.Sc. (Mrs. Harold
Haywood), see: Journal of the Institute of Metals, Vol. LVI, 1935. The graph has been edited.
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