Monac
Member
Look, with old, non-expanding bullets, kinetic energy did not matter very much. A 9mm FMJ would usually go straight through people, and as long as you were doing that, what difference did muzzle energy make? A 45 ACP FMJ might have been a little less likely to go straight on through, and that may account for its better reputation for stopping power back then - it was punching people harder.
But nowadays we have bullets that expand on impact, and it turns out that once you design a good bullet, one of the key qualities that determines how much it expands is its kinetic energy (when it hits the target, obviously, but that depends on what it started out with).
(Quick flashback to high school: Momentum = mass times velocity. Force = mass times acceleration. Kinetic energy = 1/2 mass times velocity squared.)
If you think expanding bullets don't work, well, then you've got an argument with every police department that has adopted them since the 1970's and has found out that they DO work. Don't talk to me, talk to them.
And thus we circle back to the whole reason this conversation started: Law enforcement agencies have decided they can get adequate stopping power from 9mm guns using the right bullets. They are therefore dropping the 40 S&W because 9mm is more pleasant to shoot and easier for their officers to qualify with.
So does 40 S&W have a future? My opinion would yes, because it does offer somewhat more power than 9mm, and there will always be people who want that. The analogy I think of is that back before 1945, when 32 ACP was what most people wanted in pocket autos, there were enough people who wanted pistols in 380 to make it worthwhile for Colt and Savage and Remington to make guns for them.
A better question might be about the future of 45 ACP, because it requires guns that are either bulky or low-capacity, without - in the day of expanding bullets - offering better stopping power. But I am not worried about it, because it is a quintessentially American cartridge, like 45 Colt, and THAT is still around 140 years after it was new. Cartridges take a LONG time to die, if there are a lot of guns around for them, or if people just really like them - 32 S&W Long is another classic example.
But nowadays we have bullets that expand on impact, and it turns out that once you design a good bullet, one of the key qualities that determines how much it expands is its kinetic energy (when it hits the target, obviously, but that depends on what it started out with).
(Quick flashback to high school: Momentum = mass times velocity. Force = mass times acceleration. Kinetic energy = 1/2 mass times velocity squared.)
If you think expanding bullets don't work, well, then you've got an argument with every police department that has adopted them since the 1970's and has found out that they DO work. Don't talk to me, talk to them.
And thus we circle back to the whole reason this conversation started: Law enforcement agencies have decided they can get adequate stopping power from 9mm guns using the right bullets. They are therefore dropping the 40 S&W because 9mm is more pleasant to shoot and easier for their officers to qualify with.
So does 40 S&W have a future? My opinion would yes, because it does offer somewhat more power than 9mm, and there will always be people who want that. The analogy I think of is that back before 1945, when 32 ACP was what most people wanted in pocket autos, there were enough people who wanted pistols in 380 to make it worthwhile for Colt and Savage and Remington to make guns for them.
A better question might be about the future of 45 ACP, because it requires guns that are either bulky or low-capacity, without - in the day of expanding bullets - offering better stopping power. But I am not worried about it, because it is a quintessentially American cartridge, like 45 Colt, and THAT is still around 140 years after it was new. Cartridges take a LONG time to die, if there are a lot of guns around for them, or if people just really like them - 32 S&W Long is another classic example.