My 45-70 is a home made copy of a rolling block and it weighs 11 pounds with its 32' octagon barrel. Even with planet wrecker loads and its steel buttplate ; it kicks about like a 12 gauge with duck loads. Recoil is definitely tamed by more weight. If your first experience with a 45-70 included a Ruger #3....well...great gun, but way to little weight for the power of the cartridge.
Are you sure of your dates? My research shows the slaughter of the American bison began in earnest around 1868 and was pretty much completed be 1881-82,, with over 31,000,000 animals being killed. And it is a matter of historical fact that the 45-70 did its share of the killing. At typical buffalo hunting ranges, under 150 yards, a 45-70 bullet would (and still will) go entirely through a buffalo and sail off into the wild blue yonder.. So...how much power do you need??? This, too, is fact. Clint Smith told me years ago that he would have to choose his shots carefully when he and Venturino hunted buffalo; to be sure that another animal was not behind the first. He knew his bullet would not stay inside the animal he shot. He was using a 45-70, with straight black powder and 500 gr. lead bullets.
I love the cartridge. It is cheap to shoot. It is easy to load. It's just plain FUN!