See #11.
Col. Cooper also noted that “enough gun” _must_ be capable of full penetration to assure a clean kill. That would leave enough energy to likely take down another, as happened.
Optimal results would be driving the projectile to the mid-animal to disrupt the vitals and drop the critter. I don’t recall reading Cooper say much different, as driving the round clean through both sides of the critter will leave a pelt with an extra hole! ;) Perhaps it depends on the game at hand and its dangerosity.