What some a-hat is willing to torture/waste animals with, and what's a decent, humane tool for the job are not the same thing. It's disgusting how many hunters don't care about that. A lot of guys are jerk-hunters. Unless that critter is bedded down, he can always take one step in 1/2 second, and 1/2 of a step means that you've gut shot it. If your bullet is in the air more than 1/2 second, it's an inhumane shot, if the animal is on its feet. Guess how far a 1500 fps bullet travels in 1/2 second? Flat noses, large bore slugs slow down really fast, due to air resistance.
The hide-hunters used the 50-90 Sharps, much more power than the 45-70 and didn't want to waste a lot of time on having the herd run off. They got inside 200 yds, studied the herd, and shot the "lead" cow. Without her guidance, the rest of the bison would just stand there, or only mill around. So the shooter could keep stacking them up. They had to skin those monsters, salt and haul the hides. So big wagons and teams of mules were used. They did not have days and days to mess around getting one hit. A gut shot critter could easily stampede the entire herd, and there goes a week's pay and a lot of effort.
An errant breeze means a lot more to a 45-70 shooter than it does to one usinga 300 Win mag.
Mirage is often a big factor, and the longer you take for the shot, the longer the bullet is in the air, the worse things get, typically.
Guys are full of it about such things. They practice from the sand bags, on ONE range, learning the vagaries of wind there, with windflags, "spotter" shots, etc, and then kid themselves that they can do the same things in the field, one cold shot.