45-70 Trapdoor

[JReed]

The 45-70 and 45-90 share the same rim diam so no issues there. Go slow on the trimming testing fit as you go when done you will have custom fit brass. The extra powder capacity is a function of being able to seat the bullet out farther due to the long chamber. With my custom trim brass my COAL is the same as my 2.1" brass I just have more bullet in the case with the longer brass. I can get more powder in a case than a gun with a SAMMI chamber regardless of the case used. If you reline you will end up with a chamber of modern spec.