The Navy Arms Martinis were marked on the barrels, as I recall. Had one, still remember the recoil of Keith's 45-70 load. Damned unpleasant design for hard-kicking loads. Pain of firing might be as good a limiting factor as anything. . . . I never felt I was pushing the limits on pressure with any load I was willing to shoot 5x off the bench! (Unlike the Ruger #3, where I did sometimes wonder.)

Someone--Numrich maybe--offered a conversion kit to 45-70 for the Martinis.