Sir, FWIW, I've used Unique in .44 special and magnum, .45 ACP, and .45 Colt. It's not a good choice for "powder-puff" loads, but does very well in medium to medium-hot loads.
Alliant lists Unique under shotgun powders.
Click here for the Unique page on Alliant's Web site. There's a link there to all their Unique data, listed by cartridge.
Hope this helps, and Semper Fi.
Ron H.