The .40 was developed after tests by the FBI and others to find the best overall cartridge for law enforcement. I think most members here will say: the 45 has more knockdown power, but shot placement is "king."...
Actually I believe the FBI settled on the 10mm as being the best cartridge, but so many of the agents had problems with the recoil that the backed off to 10mm light (.40 caliber).
If you can handle the recoil (and the expense) then for law enforcement the 10mm probably still is king. Improvements in barrier penetration in the last few years has reduced the edge that the 10mm has over the .40 though.
If a person was absolutely sure he would need to defend his life that day he would probably want to carry something really bad---like a bazooka.
, the 40 is slimmer so its easier to conceal than the 45 and weighs less but with the right holster and shirt, they are.
If you get one shot almost everyone will go with the 45. Multiple targets and multiple shots the 40 makes a strong case for itself.
A 9mm, .40 SW and .45 ACP have about the same muzzle energy. If the bullet stops in the target in a vital area, any one will do the job. The trick is hitting a vital area.
To maintain proficiency, you have to shoot 200 rounds or more a month - 100 to get back to baseline, and another 100 to work on improvements. That's $30 for 9mm, $60 for .40SW and $90 for .45 ACP, half as much from Wally World, much less if you reload.
How many times does one confront multiple targets? A competent shooter makes do with fewer shots.
My experience has been after the first couple shots, the perps will either run off or surrender.
Yet a marginal hit with a .45acp will likely cause more trauma than a vital hit with a 9mm.
The .40 was developed after tests by the FBI and others to find the best overall cartridge for law enforcement. I think most members here will say: the 45 has more knockdown power, but shot placement is "king."
Most law enforcement now days go with the 40 over the 45 because:
1) The knockdown power is sufficient (better than the 38/9mm) and recoil is lighter so the "average cop" has a better chance of hitting what he/she points at and making it count.
2) You get more rounds for the same loaded weight gun - again more shots without reloading means there is a better chance of getting a hit in a vital area.
3) The 40 and 45 minimize the over penetration problem of the 9mm.
dont forget one of the big issues for LE was the actual frame size and weight of the 45's. a lot of smaller framed agents and women couldnt comfortably handle it. the .40 is a GREAT cartridge and was developed specifically for maximum LE needs. it has basically the exact same speed with only a slight loss of ft/lbs. most LE cartridges are looked at in the 950 ft per sec speed for ideal penetration of various substances that officers might encounter.