Shot placement...of more than one shot (IMO)...is always going to be the biggest factor. 2 hits center mass from standard NATO .45 Ball ammo should be sufficient for just about anyone and should immediately drop the target. Have a good friend in SF. He likes to shoot (and is an amazing shot with his 1911), but is not a gun guy. He uses army issue .45. Says he’s never had anyone get back up. He’s never shot gelatin.I recollect a discussion with USMC son when he was first able to CC. (At the time, I was a staunch 1911 guy.). Son was determined to carry a full size 1911. When asked why, his reply was “.45 kills their soul”. My offering to him (he can shoot like nobody I know) was “...if I could shoot like you, I’d carry a .22.”
Today, years later, he most often carries a G19.
I’m getting to my point...which follows Blaster. Good modern ammo...any of it, will do the job IF you put it in the right place, the first time.
The best, most expensive, most highly touted ammo in the world won’t do jack or shiit if you miss.
Buying more and more expensive guns or ammo or holsters is something folks with too much money and not enough sense do. Invest in training. Practice, practice and practice some more. “Put yourself in the position to be lucky.” Muscle memory is your friend. Training is money.
Bullets of any type are just that.