Uncle, the last several Hornady manuals have loads published just for the 1895 Marlin in .45-70

It includes their 300 grain soft point to 2100'/sec and their 350 grain soft point to 1900'/sec from a 22" barrel.

I'm not sure what your .45-70 wants to do but those loads are serious medicine for a lot of big game.....some even think it's worthy of Cape Buffalo......I'm not among them but they're clearly an awesome gun!!