Pure opinion on my part- there ARE Bullseye loads in the manual for 45 Colt- but that is a REAL big cartridge case. B'eye seems to do best with lighter, cast bullets- around 200 gr. As you move up in size, I would go to Unique or 2400. There are probably better powders around- I simply always have Bullseye, Unique, and 2400 on the bench. YMMV.