The 45-90 is more gun than most want to shoot for most applications. You don't see that many 45-90's on the line at BPCR shoots, the recoil is a bit much. If you shoot smokeless in the Sharps, there is no reason at all to go with a 45-90, too much case.

45-70 is such a good choice because of a availability of all the components and what the 45-70 is capable of doing as a cartridge with either smokeless or black powder...

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