Dingelfutz;
I have not tried this. I do recall some articles in the AR concerning heat treating cast rifle bullets. The process was essentially the same as you describe for the shot. It is necessary I believe for the lead to have some % of antimony for this to work, I don't believe it will harden pure lead. In the article I seem to recall bullets cast from wheel wt metal was given a hardness very similar to linotype. Some of these articles appear in the AR cast bullet handbook, but I do not know if this is still in print or not.
