Sid Nitzerglobin
Member
My understanding, albeit wholy limited to what info I have been able to find through internet research and talking to LEOs, military personel, and a couple of medical professionals I have know over the years, is that aside from making it through the initial impact w/ skin and/or bone, penetration and over penetration has very little to do w/ stopping power from a physiological perspective.
My impression is that total kinetic energy imparted and inital shape and advantageous deformation of the round from the initial impact that maximizes the temporary cavity and hydrostatic shock are the main factors in stopping someone in their tracks.
Penetration, the size of the permanent cavity, and any tumbling/fragmentation of the round have more influence over the eventual lethality of the wound(s) vis a vis organ failure and blood loss.
In short, against an unarmored intruder using the heaviest, highest velocity JHP rounds you can find in your 15-22 will maximize it's lethality and stopping power, but it's still more likely to fill the intruder w/ lots of small holes that while being perfectly lethal if not treated immediately, aren't necessarily going to instantly shut them down physically w/ any degree of certainty (barring lucky/freak headshots that manage to cause extensive brain/spinal damage).
