Lloyd,
I have cast about 250 or so of these bullets so far. They are slow work as it is only a single cavity mold. You got to really rock and roll with it as the HP stem will cool off quickly. I used an alloy of 30 lb of ww, 10 lbs of cable sheathing, and 3 lbs of linotype. Using 19gr of 2400 out of a 5 inch S&W they came apart pretty bad at 100 yds, leaving only the base. I plan on using the same alloy with 6 lbs of linotype next time. PM me if you need a few. I will be glad to send you a handful.
Beau