since you won't specify purpose

9 for volume and social issues

40 is a solution to a question 9 answered a few years later with better bullets

40 is a good way to buy more gun parts as well if you shoot much , unless you are talking a Beretta PX4 storm they stuffed a 40 in a package built for 9 and wonder why it beat it's self to pieces.

357 , yeah I like it for a wheel gun
be kinda handy in a blackhawk with a 4 5/8 barrel to carry for targets of opportunity

shooting fast and wheel guns , I know a guy probably in the top 10 of mid west Wheel gun shooters , got multiple state championships and in multiple states. he is fast and accurate
most of the time he is rocking a 9 or 40/10mm wheel gun that holds 8 rounds in moon clips all smiths the 40/10 only holds 6 rounds, that is about as fast as it gets , if you only have 6 and they are magnum rounds you best just concentrate on making hits and making the 6 you have count.
because even speed loaders leave a lot to be desired in the reloads

if you have to pull rounds out of a pocket , pouch or belt 1x1x1x1x1x1 you could have emptied 6 more guns in the time it took to reload.

where 40 can make some sense is in wheel guns built for 10mm , you can run it in moon clips to speed reloads considerably
40gets you major power factor while being not magnum
it changes the scoring

but remember it is a game and it has a lot of game-ish aspects that do not necessarily translate to away from the game but it can really push the limits of your shooting which makes you a better shooter if you take the lessons and use them.

of course Jerry had already answered this question with 45 and moon clips

the game side of things if you push a heavy bullet slow you can make power factor

velocity x weight in grains = x /1000 = power factor
740fps x 230gr =170,200 /1000 =170.2 power factor

165 is the minimum power factor for Major , you want about 5 over so that if it is a cold day or different elevation than you built the round at and you loose a little velocity you are still at 165 so you don't give up your match points at chrono

back to , FOR WHAT

what is your intended use

a carry gun , a gun to wear in the woods while bear might be an issue , targets , what?? if many , list them in order of importance.

40 is the best of the three options

what young man does 40 do better ?

please explain.

the thing is 9 and 40 and even 45 , most all the self defense ammo gets calibrated to go minimum 12 inches in 10% gel after 4 layers of denim and go less than 16 inches in 10% gel after 4 layers of denim.

if your shooting buffalo bore , or reloading there is an exception.

so at the end of the day does .050" make a bad shot a good one in tissue , probably not

on paper maybe

but is it worth the expense of giving up 10-30% of your capacity

357. Then you can shoot 357s and 38s.

I had a truck gun a shotgun with a collection of types of shells from buck , to bird , it kicked hard but I knew where it hit and it had a c-lect choke on it

then I had a different gun stolen from a truck.
that about cured me of keeping a truck gun , yes the loss of that shotgun wouldn't be that much , when I bought it I had $75 invested in it and it worked well

so now I have door guns 22lr rifles , a 308 , a 12 ga and some 22lr pistols
they stay in the house but are set up in such a way they can grab and go and have ammo with them , pistols are loaded and in holsters as well.

I leave some additional ammo in the truck
box of slugs and shot , box of 22lr

well in my opinion its a good reliable caliber the best out of the three options for price punch and availability as well as reloading components are much easier to find. its also very easy to find a gun in that caliober for a good price with the style you desire there is many many more options for a 40 than there is a 357 magnum and 9mm handguns are going to be twice if not three times more expensive because they're mass produced by many companies and much more upgraded and complex

you are right , you can get used 40s for dirt cheap

it doesn't cost a dime more to make a 9mm gun than it does a 40 , there is just less demand and an over stock of excess 40s

so lets say you get a LE trade in 40 Glock 22 for 272.00 and a similar G17 for $349 yes the G17 is harder to find sold out a lot more often.
https://officerstore.com/firearms/used-firearms?_bc_fsnf=1&brand=441&stock_status=In+Stock


for a few reasons , the market is flooded with cheaper 40s , first departments get 1/2 the life out of them , now cops really don't shoot their guns all that often but they might go 1500 rounds a year and can expect to have to re-spring at 4500 rounds that is also a good time to put new pins in them. basically have the armorer sit down and go through them for wear
armorer time is more expensive than parts.
likewise 9000 rounds if a good time to go through your G17 for more than cleaning time for springs and a wear check.
so you went 3 years or 6 years

when you go 3 years it becomes an administrative choice to send back your guns for trade in get the credit and discount and get all new 40s
the same for the 9s but half as often.
just like you don't have them overhaul your patrol vehicle you order new ones and send the old ones to the auction. It is a fixed expense budget item.

now we go hit midway for a little ammo shopping you buy 9mm for 26-28 cents a round we will average that at 27 cents a round and 40 starts at 38-40 cents a round so 12 cent a round difference on average.
now I want a good carry ammo so I for sake of this argument and good availability chose Hornady critical duty it is available in both 9 and 40

9mm critical duty is 1.37 a round
40S&W Critical duty is 1.67 a round


so you buy your 272 dollar gun and fire 250 rounds of practice ammo through it then 50 of your defensive ammo , now you are ready to carry

G22 40 cal $272
250 rounds @ 39 cents a round = $97.50
100 rounds of SD ammo @1.67 a round $167.00

536.50

G17 9mm $349
250 rounds @ 27 cents a round = $67.50
100 rounds of SD ammo @ 1.37 a round 137.00

553.50

I agree in the first purchase and getting ready to carry , the 40 is 17 dollars cheaper and that will almost pay for your first recoil spring they run 20 dollars and the 40 uses 2 of them for every 1 the 9 does

but they both go between 12 and 16 inches in 10% ballistics gel

now if you intend to do what a vast majority of people do , buy a gun and toss it in the drawer for some day with a few boxes of ammo you will see a much greater savings

on the other hand if you shoot 1500 rounds a year to maintain a level of proficiency and buy 100 new rounds of SD ammo each year

9mm will cost you 542 dollars a year
40 will cost you 752 dollars a year and a recoil spring and whatever else you break.

I didn't even get into how the 40 is shown harder for a majority of officers complete the course of fire for annual recertification.

X2. Can never have enough guns.

Let me say it before 160 does !

The 9mm is perfect for woman and small children.

I am also going to disagree with this.

when your looking at purchasing your 4th big safe and you are looking at your inventory and thinking man there are guns I haven't shot in 5 years and I really have lost interest in , I pull them out and wipe them down once a year and that is turning into a chore more than a pleasure , then you might be getting too many guns

now there is no number that is right or wrong

what seems fair to me is 1 for everything you want to do , a backup or two for the things you do often or need to do and some for sentimental sake.

when you start asking yourself do you own your stuff or does your stuff own you , maybe it is time to let a few go to someone who could use them.

X2. Can never have enough guns.[/quote]
I am also going to disagree with this.

when your looking at purchasing your 4th big safe and you are looking at your inventory and thinking man there are guns I haven't shot in 5 years and I really have lost interest in , I pull them out and wipe them down once a year and that is turning into a chore more than a pleasure , then you might be getting too many guns

now there is no number that is right or wrong

what seems fair to me is 1 for everything you want to do , a backup or two for the things you do often or need to do and some for sentimental sake.

when you start asking yourself do you own your stuff or does your stuff own you , maybe it is time to let a few go to someone who could use them.
[/quote]
general rule of thumb for a happy gun owner is one gun for every other year you've been alive. I'm still trying to get there

think about it this way , some where about 50 if you give yourself 10 minutes a gun to access it pull it from it's sleeve , wipe it down and check it over you have an 8 hour day in.

when I was doing all the youth shooting sports guns , getting them ready in the spring and putting them away , it can start to turn into a real chore.

I have far more guns than years I've been alive. I don't think I'll live long enough for my age to catch up to my firearm purchases. Still don't own a single .40 s&w. I have a few 10mm's (also a .40 cal barrel, but with a less anemic powder charge)

Yep I always favored a S&W huge selection of store bought stuff and reloading components I've loaded 360 roundballs over a case full of pyrodex to 180's with 4227 for a thumper If I was limited to 1 handgun it'd be a k frame 4 inch barrel smith
mite not be big bear medicine but if you dont tell the deer they'll never know