i shoot 27grs imr 4198 with a 300gr cast bullet(no filler) for 1200-1300fps in a 1876 made in 1883. its four inches high at 50yds and right on at a 100yds. with your rifle made with modern steel you could go a little higher and also use jacketed bullets. cases are easy to make,shorten 45-70 cases and you may have to thin the rim a little. i took a 45-70 seat-crimp die and had it shortened 3/8 inch(it still can be used on regular 45-70,s) to seat and crimp the 45-60,s. eastbank.