It doesn't take much antimony added to lead to hold the setback. My favorite alloy is a mix of 17# lead and a one pound of no lead solder, 95/5 tin antimony or one roll in 18# for the .45 PP I shoot in it. One thing to keep in mind when you switch to a PP that is patched at or slightly below bore the super hard bullets are not malleable enough to fill the grooves for proper rotation in a lesser caliber. For the GG it is a lot more forgiving to have it at groove or a thousand or two over groove.
This .44/.432" bullet was patched .001" over bore and cast with 1# roll of no lead solder and 17# lead behind 93gr of 1.5 Swiss.
http://i704.photobucket.com/albums/w...ps1xzzesje.jpg