We may want to open this discussion up, to include answers to the original question.
My quick answer - the .380ACP load that penetrates to 12.0" or deeper in 10% ballistic gelatin and expands. Next up would be the load that does not expand and penetrates to 12.0" or beyond.
So far, out of 2.75" barrels, the Federal 90gr Personal Defense Hydra-Shok expands and penetrates adequately. Everything else .380 that I have tested either expanded too much and penetrated too little, or did not expand at all.
Hope this helps ...