I don't understand why anyone would risk hunting with a marginal cartridge, if they have other options available.
While working for a wildlife agency, I've had to take a few big game animals with a .22LR, because, I simply had no other choice at the time. (To protect motorists, end suffering, etc.)
"Stunt Hunting" is foolhardy, unethical (IMO), and potentially dangerous for everyone involved.
If the only rifle I had was a .257 Weatherby, I was a resident of Africa, and if I needed to defend myself, feed my family, or protect others, that would be a different story.
But, to carry a .257 Weatherby to Africa from a distant country, pay big money, just to prove I can kill a buffalo with it is, (IMO) absurd. I have no doubt, that I could do it, but I don't understand why someone would want to try.
I also feel that way about handguns in typical handgun cartridges.
I, personally, wouldn't hunt buffalo with archery equipment, but I feel like a very experienced bowhunter, could work up the right combination of bow, arrow, and broadhead to make it "ethical".
With that begin said, if I wouldn't take the shot without a PH with a big stopping rifle at the ready, I don't think I'm not sure that I would not be "stunt hunting".
Again, it's just me.....