I'm about ready to start working up loads for the new Ruger GP100 10mm. I have the Lipsey's edition, 5.5" barrel. I have a supply of Rimrock 220gr cast. I'd like to get what I can out of them, Underwood and Buffalo Bore are getting 1200fps. Underwood Pulldowns have yielded 800x and Longshot. Two powders I have on hand are 800x and Blue Dot. Longshot and Power Pistol and AA#9 appear to be the other popular choices for experimentation. I'm not opposed to buying them.
If you have done this, you know about the scarcity of data. Anyone else messed with these? Appreciate any related experience.
