I played around with various powders, including some judicious use of TP filler (in consultation with John Kort) working on a good smokeless load. In the end, I just settled on Unique with a 215 grain cast bullet. There is some velocity spread depending on the position of the powder, but I honestly can't see a major difference on the targets. When I bench my rifle at longer distances, I may see some issues, but in the end, I'm just plinking from under 75 yards and don't really see enough of a difference to warrant the trouble. I had fun playing with different powders and loads, but I can't say that the improvement over a classic Unique load was enough to worry about. This isn't a benchrest cartridge or rifle. I mainly just go up against the Campbell's or DelMonte gangs when they get a little rowdy.
Griff
PS: I have always just used standard large pistol primers, which have worked just fine for me.