Here's someone making the argument for the switch.
Why Nine? - Full30

It really doesn't matter. Personal preference is all.

Carry what you can shoot effectively......Repeatedly.

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Life Is A Gift. Defend it!

Just another opinion piece like the others that have been around for years...just like discussions on recoil and powders.

All the service calibers perform about the same. Pick what you like. Personally, I like 9mm, mostly because it's probably the least expensive ammo nowadays (might not be an issue for those who reload their own ammo). Plenty of 9mm JHP loads with both a proven track record in actual shootings and good performance in gel. Generally speaking, given the same type of gun, it'll be easier to get quick hits with 9mm than bigger calibers. I consider capacity and wear-and-tear issues to be less important.

But there's nothing wrong with the other service calibers. Like I said, pick what you like.

No, no, no. If you carry a nine +p it's too small and all it does is over penetrate. You need a .45. Got the .45, good, no, bad. Bad .45 not as many rounds and they are slower. Have to try .40, .40 is the ticket. Oh, no, its not .40 is a compromise! All compromises are bad. Get a ten, no compromise there. Lots of testosterone. Grrrreat, and it works in the 1911. Slower follow on shots. Well heck, if you are carring something smaller and faster than a .45 in a 1911, shouldn't it be .38 Super, fast follow on shots in an almost .357 level round. But wait, if you want .357 performance, why not .357 SIG, and you can get a double stack mag that still fits into your hand, good. But you know what's better? Nine Parabellum +p its like .357 SIG, but MORE ROUNDS.

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Certified Curmudgeon

Bullet technology has come a long way in the past 30 years...so much in fact that for the most part, 9mm, .40, and .45 really no longer matters, they all perform well.

Like everyone else is saying, this is old news, and a tired discussion. Carry/use what you can shoot best, end of story.

Personally, I prefer a phased plasma rifle in the 40 watt range.


Seriously, with modern bullet designs I think it boils down to exactly three things.
1. What caliber can you best shoot.
2. If carrying concealed, what can you best conceal.
3. Magazine capacity, if that really concerns you.

Beyond that, with proper shot placement, there is little difference between 9x19, 40 S&W, and 45 ACP. I'm happy with 13 rounds of 9x19, I'd be just as happy with 8 rounds of 45 ACP.

Given a choice, I'd go 12 gauge and 00. That not being convenient or socially acceptable, I carry a .45.

I did it !!!!

Put my Shield 45 in the bedside table...and the new Shield 9 2.0 in my waist.....

Ask me why and I will tell you this......I just wanted another Shield.....

Love both....shoot both well....but really did want a little more capacity for everyday carry .... Stupid idea I know as I hope never ever have to use a SD EDC weapon.

In short...what you goona do ? Who you gonna call ?
Make yourself happy and all others can go squat on a log...

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Hipcocked45

I have been going from 9mm, .38, and .357 to the .40, .44 and .45 just because its easier for me to see the bigger holes in the targets with my aging eyes.

Like the old Texas Ranger, I carry a Colt .45 because Colt don't make a .46.

I guess that isn't much of an excuse these days since there actually is a 1911 sort of gun in .50 but I find that a bit too expensive both to buy and to feed.

I've been a student of ammunition effectiveness for over 50 years and have shot a lot of stuff that bleeds, and have a bunch of students who have shot a bunch of people (mostly military though) - I see a big difference in performance between the calibers when shot well - not so much if one is just satisfied with "torso hits" or "center mass" hits (those don't work too well with anything, unless the "shootee" is predisposed to quit the fight - fortunately the vast majority are so disposed)

Just Ramblin'

Riposte

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"Adventure is the result of poor preparation"

A well respected firearms author wrote many years ago that he kept a 22 on his nightstand. Why? Because at 3AM, being woken from a sound sleep, he knew he could put 6 shots in the forehead of anyone evil doer. No big muzzle flash, no recoil, to blasting. Just putting them where they need to be. Right or wrong, that's what he wrote.

First off, I don't really understand this debate, though I actually came here today looking to start my own thread on it, sort of. For me, it begins with the gun.

A 1911 changed my life that day I first fired it. At the time, I was taking a self defense class, using a Sig P226, which I loved. Truth is, the P226 didn't fit me. Now, when I say fit, I could shoot it well enough at the range, but reaching all controls during strings of fire, etc., was not "easy".

So, before finding the round, I decided to look for the gun.

No polymer - why? First, I like the look and feel of steel. Important? Perhaps, as I believe attitude and confidence is very important, should you need to use the gun to defend yourself. This is not a statement about possible failure of polymer, etc. Not at all. Younger generations might feel very confident in their polymers, but old guys prefer to sweat the pipe, as opposed to PVC ; )

1911 - I have a couple in 45, will never sell them. Should I get them in 9mm, perhaps.

EAA Witness - older all steel model, 40 S&W. One of the few guns I've found that, for me, properly tames the 40 S&W snap. But the grip is a tad bigger, thus controls less friendlier than the 1911.

Springfield P9C - 40 S&W - A compact version of the Springfield P9. Those unfamiliar, these were made int the 80s from Tanfoglio parts, polished and fitted to near perfection. They are considered to be the best of the CZ clones - no surprise since the were produced under the direction of Les Baer, during his time leading production at Springfield Armory. The gun is all steel, very accurate, and eats up the 40 S&W with no snap. Possibly the prefect carry pistol in 40S&W - but I only have one and they aren't making anymore. I've owned the P9C 9mm as well, but the grip was too fat.

Sig P239 - 9mm Love the gun, but I do find that even with pinky rest, the grip is still a bit short for me. Can I shoot it well, you bet. But in an emergency will that short grip be an issue?

S&W 3913/3953 - Now we're cooking with gas. 9mm, single stack. I can reach of the controls easily, gun is accurate, grip fits my full hand. I guess there just isn't enough of a market for steel guns, or S&W would still be cranking these out.

Sig P938 - as a pocket 9mm, this gun is very accurate and with Hogues this gun makes a nice backup or pocket gun for me. The guide rod hitting the bad guy in the forehead is a plus...Geez Sig, get your act together.

Lastly, I have other shooters in the house, who are now shooting 9mm, so logistics becomes part of the conversation. Buying/reloading ammo, sharing ammo or even magazines, in a defensive situation, etc. all come into play.

So, for me, the CCW takes me to 45 or 9mm and logistics narrows it down to 9mm. I've seen the newer CZ compacts in 40, but they have rails and/or are a bit bulky. I'll stick with my 3913 in 9mm, or perhaps a 1911 in 9mm. IMO, where defense is concerned, a handgun is simply better than nothing. 9mm/40/45 isn't really going to decide the outcome nearly as much as training, attitude, strategy, being prepared in advance.

Thanks for listening and helping me answer my own question. I believe I'll be selling off my 40s, or perhaps looking for 9mm conversions for them.

Heck, people die from a "Poor Shot" from the little .22 ............
you never know where that little bullet will end up !!

What ever works.

For me it's more platform than caliber. I regularly carry either a 380, 9mm, 40, 45, 38 Special, 38 S&W, 9mm Mak or 22 LR, depending on what I'm wearing and where I'm going.