A very good reference that covers all the BP carriage data and rifle types is, "Shooting Buffalo Rifles of the Old West ", by Mike Venturino. This book includes the cartridges mentioned by the OP, complete with loads and velocity data. Looking at a lot of the posts in this string, the inputs can put you all over the map. Is the OP interested in formal BPCR shooting, informal targets, hunting, etc. The rifles and calibers used in BPCR fall into a specialized form of shooting sport. Comparing modern designs using smokeless powders to period BPCR may be analogous to comparing a traditional longbow to a modern recurve, or compound bow......very different animals. IMHO.