The 40 cal is a niche cartridge that gained favor when the feds couldn't qualify with it and they needed something a bit fluffier than the big bad 10. On one hand they can cite the need for controllability and less frequent pass-throughs and collateral damage but the truth is there were simply too many fbi types who could not handle or manage the 10. And the Miami shootout was a lesson in tactics, not firepower. The ammo used in the 9mms simply failed to immediately incapacitate - it finally managed to kill, but did not stop immediately. Don't forget that the Winchester 9mm ammo used by the fed (Silvertips)was designed to expand and not penetrate t&t, following the fallacious notion that such would stop a gun-slinging criminal immediately but it was the ammo that failed. The killer who took 3 hits to his chest with that ammo finally died after being head shot but it was the ammo, and of course the fbi tactics at the time, that failed.
I believe the only reason for the success of the 40 S&W is its police use. For some reason many agencies believe or feel that the 9 is insufficient and the 45 too big. The 9 has never been insufficient but the 45 may well be too big for many officers to effectively qualify. I have used the 9 on the battlefield and it works - I have never seen anyone walk away from a double tap to the chest even with ball ammo; 3 rounds at the most if you don't want them falling on you and blowing blood all over you in the process.
When I hear of the 9 not working in Irag/Afganistan I kind of wonder why, when it worked before and I simply do not buy the idea that the middle easterners are bigger and badder than the VC/NVA were. Let's not forget what the 9 did to our guys during WWII.
I have always felt it is not the size of the bullet but placement that counts. I don't carry a 9 that much because I don't own the pistol I prefer, but I may, soon. jmtcw.
