These threads are always entertaining, speaking lever rifles the c.o.a.l. length is always a major concern.
That being the case, bullets of 500 grains plus or minus a bit are used from .458" to .512", my '86 Turnbull 50-110 WCF fires 525 gr WFNGC bullets at 1855 fps, my old Marlin Cowboy in 45-70 threw a 525 gr Beartooth piledriver to 1755 fps.
Of like construction, bullets from the 45-70 will out penetrate the larger bores, bullet SD is still king when all things metallurgical and velocity are matched.
IMHO, once you reach .458" there isn't a critter alive that will know the difference.
