I've owned a number of 10mm's and I've loaded for it and the .40 for years, and to me the .40 is better overall than the 10mm is. Of course, everyone is different but I'll tell you why I don't see 10mm as being worthwhile.
Price. Yes it's cheaper and unless you've got a real sweet source of cheap 10mm brass, the .40 will be a lot cheaper to reload for, plus it doesn't eat quite as much powder. If you don't reload, .40 is definitely cheaper and it has better options for self defense use.
But on to the main issue...power.
It's true there is no such thing as a .40 +P, not technically at least. It's a marketing term to differentiate what one would call "typical" .40 ballistics compared to warmer .40 loads that produce better ballistics. There isn't a 10mm +P either, but a 180gr at 1350 FPS could very well be considered, from a marketing perspective, as 10mm +P because that's pretty much max from something like a Glock 20.
One aspect that many don't realize that these places (Underwood, Buffalo Bore, etc) do pay the 10mm special attention. What I mean is that their 10mm is about as hot as you're going to get even if you handload. They don't afford that luxury to every single cartridge they offer, they know only top end 10mm sells, so that's why they do it.
I've compared warm .40 and warm 10mm reloads and what I've found is that 10mm is faster, but not that much faster. Comparing Longshot, using factory data I got about 1270 fps with a 180gr from a Glock 20 and about 1250 fps with a 180gr from a Glock 35 .40 S&W. If you want to get a well supported barrel you can get the .40 S&W to run a 180gr past 1350 fps from a 6" barrel and over 1275 fps with a 200gr. My point simply wasn't to make the .40 a 10mm, but just to see what the .40 will do, and if you want it to, the .40 can do, realistically, anything the 10mm can. I don't mean match it on velocity, as the 10mm can be loaded about 100 fps faster than the .40 with similar length barrels, but in simply questioning what colossal difference that 100 fps will make, and I can say that nothing living will know the difference.
That said, many don't reload and as such, the only way to get close to those numbers is to buy 10mm. I also believe that many overthink it, and what I mean is, a factory 180gr .40 S&W @ 1000 fps will kill deer and hogs all day, even black bear. For dangerous game I wouldn't want either one, give me something considerably bigger. I simply think that for what 99.999% of what most people would ever need a gun for, the 10mm won't do anything the .40 won't.
I'm a Glock guy, and although I've owned multiple 20's, 29's and a few G40's, I just don't care for the size. I can tolerate the G20/40 but the 29 feels wrong to me. I much prefer the size the .40 Glocks, which are the same size as 9mm. This isn't to talk negatively of the 10mm, I have two, my mindset is that the .40 is cheaper, it shoots the exact same bullets, it's got better ammo choices and if I want to load it up hotter, it's nearly a full power 10mm on a 9mm sized platform. That's enticing to me.
Price. Yes it's cheaper and unless you've got a real sweet source of cheap 10mm brass, the .40 will be a lot cheaper to reload for, plus it doesn't eat quite as much powder. If you don't reload, .40 is definitely cheaper and it has better options for self defense use.
But on to the main issue...power.
It's true there is no such thing as a .40 +P, not technically at least. It's a marketing term to differentiate what one would call "typical" .40 ballistics compared to warmer .40 loads that produce better ballistics. There isn't a 10mm +P either, but a 180gr at 1350 FPS could very well be considered, from a marketing perspective, as 10mm +P because that's pretty much max from something like a Glock 20.
One aspect that many don't realize that these places (Underwood, Buffalo Bore, etc) do pay the 10mm special attention. What I mean is that their 10mm is about as hot as you're going to get even if you handload. They don't afford that luxury to every single cartridge they offer, they know only top end 10mm sells, so that's why they do it.
I've compared warm .40 and warm 10mm reloads and what I've found is that 10mm is faster, but not that much faster. Comparing Longshot, using factory data I got about 1270 fps with a 180gr from a Glock 20 and about 1250 fps with a 180gr from a Glock 35 .40 S&W. If you want to get a well supported barrel you can get the .40 S&W to run a 180gr past 1350 fps from a 6" barrel and over 1275 fps with a 200gr. My point simply wasn't to make the .40 a 10mm, but just to see what the .40 will do, and if you want it to, the .40 can do, realistically, anything the 10mm can. I don't mean match it on velocity, as the 10mm can be loaded about 100 fps faster than the .40 with similar length barrels, but in simply questioning what colossal difference that 100 fps will make, and I can say that nothing living will know the difference.
That said, many don't reload and as such, the only way to get close to those numbers is to buy 10mm. I also believe that many overthink it, and what I mean is, a factory 180gr .40 S&W @ 1000 fps will kill deer and hogs all day, even black bear. For dangerous game I wouldn't want either one, give me something considerably bigger. I simply think that for what 99.999% of what most people would ever need a gun for, the 10mm won't do anything the .40 won't.
I'm a Glock guy, and although I've owned multiple 20's, 29's and a few G40's, I just don't care for the size. I can tolerate the G20/40 but the 29 feels wrong to me. I much prefer the size the .40 Glocks, which are the same size as 9mm. This isn't to talk negatively of the 10mm, I have two, my mindset is that the .40 is cheaper, it shoots the exact same bullets, it's got better ammo choices and if I want to load it up hotter, it's nearly a full power 10mm on a 9mm sized platform. That's enticing to me.
