I'm awaiting delivery of a "NIB Miroku Winchester 1873" in 45 Colt. I've never loaded for this caliber but have all the components and am trying to stay within the necessary parameters of the fragile 1873 action. (Max pressure 14,000)
Here are the powders I own along with the manufacturer's published load data. All my starting loads are invariably manufacturer's "minimum loads" and then I'll work up from there. I'll solely be using this gun (and, likely a companion Colt SAA) for punching paper and ringing gongs. It will likely not even see range time more than a few times a year.
My actual bullet is X-treme 200 grain plated and X-treme's caveat is to keep the velocity to no more than 1,200 fps.
Anyway, here are the powders. I'm leaning toward either #5 or the N330. I use a Dillon progressive and like it when the volume of powder is such that I can spot an accidental charge right away.
Powder Bullet Min load Velocity Pressure Max load Velocity Pressure
VihtaVuori N330 200 gr LRN 8 876 N/A 8.6 978 N/A
Winchester 231 200 gr LRN 5.9 761 5,800 8 1002 13800
Winchester 231 200 gr XTP 7.8 956 11000 8.7 1048 14000
Hodgdon Titegroup 200 gr LRN 6.5 933 9300 7.7 1050 12700
Hodgdon Titegroup 200 gr XTP 6.7 899 9600 7.5 989 12700
Accurate #5 200 gr XTP 10.4 908 N/A 11.5 1032 13400