Yes, I was planning to use standard .45colt loads.

I've used this technique for years for .357mags and .44mags (using .38spcl and .44spcl load data, respectively). Usually a "special" max powder charge is a REALLY comfortable "Magnum" load, so I typically just start with the max charge from the "special" section, and start tweaking up and down to get it grouping better.

The good news about the .38spcl/.357mag and the .44spcl/.44mag is that 1) the powder charge isn't THAT different, and 2) they both use the same primer. However, the .45colt/.454 Cassull spread is pretty big on powder AND the .454 Cassull uses small rifle primers, instead of large pistol. I'm assuming if I use .45 colt data for Cassull cases, I'll have to swap over to large pistol primers (or maybe magnum pistol primers). .454 cassull cases are also thicker (especially case head), so I'm worried they may not properly expand into the chamber under lighter pressures.

But I'm guessing there is someone out there that has done this and can weigh in?