This is from DocGKR an expert in the ballistics.
"Many small, easily concealed semi-automatic pistols which are recommended for law enforcement backup or concealed carry use fire .380 ACP or smaller bullets. While these small caliber handgun bullets can produce fatal wounds,they are less likely to produce the rapid incapacitation necessary in law enforcement or self-defense situations.
Handguns chambered in .380 ACP are small, compact, and generally easy to carry. Unfortunately, testing has shown that they offer inadequate performance for self-defense and for law enforcement use whether on duty as a back-up weapon or for off duty carry. The terminal performance of .380 ACP JHP's is often erratic, with inadequate penetration and inconsistent expansion being common problems, while .380 ACP FMJ's offer adequate penetration, but no expansion. All of the .380 ACP JHP loads we have tested, including CorBon, Hornady, Federal, Remington, Speer, and Winchester exhibited inconsistent, unacceptable terminal performance for law enforcement back-up and off duty self-defense use due to inadequate penetration or inadequate expansion. Stick with FMJ for .380 ACP or better yet, don't use it at all. The use of .380 ACP and smaller caliber weapons is really not acceptable for law enforcement use and most savvy agencies prohibit them."
While this may not include some of the more recent loads, it's sound advice.
