Is the 45-70 of which you speak the same as the 45-70 Government?
Same thing. It’s a leftover cartridge from the age of black-powder cartridges in the late 1800s, the name basically meant 45 caliber, 70 grains of black powder. Antique guns and replicas still shoot that sort of load; nonetheless when you load 45/70 ammo with modern smokeless powder, you’re talking about a bullet weighing 300 - 500 grains moving at 1500 - 1800 fps, and it’s not a tail-heavy bullet so it doesn’t veer or yaw going through large animals.