This is an interesting tool that Winchester has up on their web site to let you compare the results from different types of their Ranger law-enforcement ammo.http://www.winchester.com/SiteCollectionDocuments/flash-SWFs/law_bullit.swf
One take-away I got from it is that pretty much all of the "big 3" (9, 40, 45) will get the penetration and expansion needed for effective self-defense purposes.
Sadly the little 380 seems to lack in penetration compared to the others. I guess that's the tradeoff you have to make for concealability. Still with good shot placement it looks like it would do the job.
Even though Winchester Ranger ammo is marketed to law enforcement you can often pick it up at a good price through on-line ammo sites like www.ammunitiontogo.com
, and www.cheaperthandirt.com
I've got a number of boxes of the Winchester Ranger and also some Federal HST ammo stored away.