I teach a high school forensics class at a Christian prep school.
We use a police DVD to show the difference in the stopping power of different calibers and loads. (Targets were a combo 1x4 wood plank and water filled milk jugs.)
Their conclusion was to go for the highest velocity round for “your” most accurate caliber.
Highest velocity isn’t always the answer, like another poster said, shot placement obviously counts, but also a slow heavy projectile can inflict more damage in some cases, especially if one is wearing body armour. For example, a shotgun slug to the chest if a person is wearing body armour will have a great effect, or a shot to the helmet, likely still break necks. Even the Americans in WWII found that they would shoot a german in the head with the .45 and it wouldn’t sometimes penetrate the helmet, but the german was dead anyways... the force of the hit breaks the neck.
Energy = mass x velocity SQUARED.
The trick is to choose a bullet which transfers all of that energy to the target without over or under-penetration.
Glasers can fragment too fast in some applications, and FMJ rounds tend to go thru without complete energy transfer.