I'm with Doug on the above. A good 250-255 cast boolit on top of 8 gr of Unigue. I chronographed some Winchester and Remington Factory 45 Colt 255 gr loads (not the neutered cowboy loads) and this load of Unigue duplicates the velocity 850-890 fps in my NM Vaqueros, one a 4 5/8" and the other a 7 1/2" barrel. Give or take a few fps, this is the same as the old standard black powder load that made the 45 Colt famous. You can go up to 9 gr./Unigue if you wish easily.
It is also a very deadly load, as it will completely shoot through a deer at any range you may be able to hit one. I say this from experience, not just blowing wind!