Nomercy:

You may have a better load for the 45-70 Gov., but this is just what I have experenced. What data I have found on the 450 Marlin, shows it is faster than the 45-70 Gov. using Marlins M 1895. There two guys (both handloaders) who compete against each other at local range; one has a 450 Marlin, and the other has a 45-70 Gov. both are M 1895's. The Marlin 450 usually (but not always) beats the 45-70 Gov. by only about 125 f/s. One day a fellow came buy with a Browning 78 in 45-70, and blew them away by about 450 f/s. I once had a chance to buy a Browning 78 in 45-70 (at about 99 percent) for $650.00, but I didn't act fast enough; I kick myself every time I think about that. Good luck.