I would very much like to see a documented case in which someone took a shot from a .460/.500 S&W Magnum or a 12 Gauge Magnum Slug center mass and kept on coming.
Seriously, I have no difficulty believing that most handgun, rifle, and to a lesser extent shotgun shells loaded with buckshot can fail to result in a one-shot-stop, but I find it hard to believe that some of the largest caliber magnum handguns, shotgun slugs, and especially large caliber rifles have failed to immediately end a fight by means of incapacitation or death.
So if anyone could provide links to some articles involving cases in which a criminal took a center mass blast from big bore magnum handguns, shotgun slugs, or big bore rifles yet persisted in attacking.
Honestly, that would be an eye-opening experience.
That being said, it is to my understanding that the closest thing to a one-shot-stop which can be had without scoring a direct hit to the brainstem is a shot to the pelvis with a bullet powerful enough to break it, because obviously this makes them physically incapable of standing/walking.