I always had trouble with straight-walled cases like the 45-70. After you resize, you have to run it through a second die to flare out the case mouth before you can seat the bullet. Too much, the bullet won't seat firmly. Not enough, and you will crush the case in the press when you seat the bullet.

I found any bottle neck rifle cartridge is the same to reload. Although little ones like the 222 Rem are a little more of a PIA. To me at least.

I reload for a 7mm Mag, 300 Win Mag and a 300 Wby Mag and have no more difficulty resizing than I do with my 308, 30-06 or 25-06.