Kahr .9mm vs Kahr .40mm

[Theohazard]

Marginal at best? Then why do many police departments use the 40? Its not cause its cheaper, or easier to shoot.

They use the .40 mainly because of perceived deficiencies with the 9mm. Often undertrained police officers fail to place their shots consistently, resulting in a failure to stop the threat immediately. Switching to the .40 is often a bureaucratic fix for a problem that results from a lack of training, not a deficiency in the 9mm round itself. However, many departments around the country are starting to realize this and have been switching back to the 9mm in recent years.

[Theohazard]

Even if it is just marginal.. I'll take it.

And that's why the choice between 9mm and .40 usually just comes down to personal preference. With, say, a Glock 19 I like how I can accurately place my shots faster than I can with a Glock 23. That, and I have two extra rounds in the magazine "just in case". You, on the other hand, like having a round that is slightly more effective per shot. There's nothing wrong with either approach.

[Cheapshooter]

Kahr .9mm vs Kahr .40mm

My first impression by the title of your thread, and using .9mm and .40mm is that you may well need to study, and learn more about firearms before you decide on either.

Now if that was a typo that you didn't catch, I'd say you need to try and find a range that rents guns, has both, and try them. I do carry a KAHR CM9, and it shoots very well. I also have a Springfield Armory XD40 Subcompact that is somewhat larger, and heavier chambered in 40 S&W. I am very tolerant of recoil, but do notice a sharper, and more pronounced recoil and more muzzle flip with the larger XD in 40 S&W over the Kahr CM9. I see nothing in the design of the KAHR that would reduce recoil, so I would think that the CM40 would have considerably more recoil than the 9mm version. I haven't shot a CM40, so I don't know for sure. But my CM9 does have more noticed recoil than my larger, and heavier 9mm pistols using the same ammo.

[10mmAuto]

Then why do many police departments use the 40? Its not cause its cheaper, or easier to shoot.

Because they buy the same false dichotomy you do. You're talking about the police, not DEVGRU. They are not exactly huge experts on... anything relating to firearms.

Even if it is just marginal.. I'll take it.

Sure, you're giving up a fair amount of "shootability" and a marginal amount of capacity in the process though.

As far as data goes to "prove" what's better, the hardest and least interpretative data is energy. 9mm, .45ACP and .40S&W all fall in the same energy range if you look at a wide selection of available loadings. The fact that it's so easily debatable one way or the other which (.40, .45, 9mm) is better demonstrates how even their capabilities are.

[Dashunde]

Sure, you're giving up a fair amount of "shootability" and a marginal amount of capacity in the process though.

I'd agree with that when comparing a PM40 to a PM9.
I think the PM40 is just too small for good amounts of practice to be tolerable.

Shootability is relative - the 40 bothers some and not others - in a pistol larger than the PM's I don’t think I'm giving up a fair amount of anything with 40.
I shoot my Glock 27 more accurately and rapidly than my PM9.

[Theohazard]

I shoot my Glock 27 more accurately and rapidly than my PM9.

Of course you do, most people would; but that's because of the differences between those two guns, not because of caliber. The Glock 26/27 is bigger, wider, heavier, and has a better trigger than the Kahr PM9/PM40, of course the Glock will be easier to shoot compared to the Kahr, regardless of whatever combination of calibers you're using. However, most people are going to find the Glock 26 easier to shoot than the Glock 27; just as most people will find the PM9 easier to shoot than the PM40.

[papadork]

My first impression by the title of your thread, and using .9mm and .40mm is that you may well need to study, and learn more about firearms before you decide on either.

I definitely didn't type the subject correctly. I do have enough common sense to shoot both and see how I like them. It's a lot easier said than done finding a range in my area that has both guns to rent. So, I was hoping to get some good input from you guys.

BTW, do people usually fight so much on this forum?

[Theohazard]

BTW, do people usually fight so much on this forum?

There are a lot of spirited debates here, but they rarely get ugly.

[papadork]

Thanks, I'll stay alert.

[Cheapshooter]

It's a lot easier said than done finding a range in my area that has both guns to rent.

Possibly you could rent a 40 of any manufacturer at least close in weight, and size to the KAHR. Then you will have a little hands on experience with the recoil of that caliber.

I heard that the CM40 doesn't have much muzzle flip like other 40's.

I take from that statement that you are at least somewhat concerned with recoil. As I said before I have not shot a CM40, but by comparison I will say there is an obvious increase in recoil in my CM9 over some of my other 9mm guns, although larger. like a Beretta 92fs, Star B, Walther P1, and FEG P9RK.

[10mmAuto]

Shootability is relative - the 40 bothers some and not others

No, it's not relative, everybody puts up better split times with 9mm. .40 muzzle flip doesn't "bother" me, but whether it does or not it's increasing the amount of time between bang, bore axis dead level, bang.

[papadork]

Possibly you could rent a 40 of any manufacturer at least close in weight, and size to the KAHR. Then you will have a little hands on experience with the recoil of that caliber.

I forgot to mention that I did that. The gun was a .40 all-aluminum S&W DAO, not sure of the model. The kick was rough and the muzzle flip was ridiculous. I just heard that the CM40 had a lower bore axis than other 40's so the flip wasn't as bad.

I'm not afraid of the recoil, (I shoot a .357 GP100 with 125g FMJ's without much of a problem) but if takes too long to regain the site picture, maybe the 9 is best.

[Venom1956]

BTW, do people usually fight so much on this forum?

Because these thread would be far less fun and far less interesting if we didn't!

Also the crabby ol' TFL vets need to bicker with the newer members. It's just how it works. Usually its in good fun.

That said I'd strongly recommend the Kahr in 9mm. I'm not a huge .40 guy though. but the Kahr in 9mm is quite controllable and has less of a learning curve. I'm not sure how experienced you are in firearms but that's my 2 cents

[Dashunde]

No, it's not relative, everybody puts up better split times with 9mm

Ugh.. your annoying. Will argue every little detail or symantic

You have provided absolutely nothing to demonstrate that 9mm, is actually, just as damaging and effective as a 40. Nada. Nothing. Zip. Zilch.

Until you do... I'll keep looking at the photo that shows the little 9mm wound channel compared to the big wound channels of the 40, 357sig and 45.

Go ahead.. keep telling yourself and anyone who will listen about how the milliseconds in 9mm split times really matters much.

I'll remained concerned with making my first shot count, you keep worrying about your second, you'll probably need it.

FWIW.. I love my little PM9, I think the round matches the pistol very well.

[Theohazard]

There's nothing wrong with you preferring the .40 over the 9mm, but you keep posting that photo over and over again like it actually proves the .40 is far better ballistically. If a round's purpose was to make the largest wound channel in gelatin, then yes, the .40 would be much better than the 9mm. But the purpose of the .40 is to put an attacker down in as few shots as possible. And in actual real-world shootings the .40 has proven to be only slightly more effective shot-for-shot than the 9mm. This is not something I've come up with on my own, this is the consensus of firearms experts the world over.

You can state your preference for the .40 and I won't argue with you. But when you say that photo proves the .40 is far better than the 9mm, or when you say "shootability" isn't an issue because your larger Glock .40 shoots better than your smaller Kahr 9mm, you're just using ridiculous arguments.

[Dashunde]

And in actual real-world shootings the .40 has proven to be only slightly more effective...This is not something I've come up with on my own, this is the consensus of firearms experts the world over.

I'm from Missouri - Show Me this "consensus".
I keep hearing about how 9mm generates the same results as the other calibers, but I see no data, no quotes from these experts. Again.. nothing, nada, zip, zilch.
The way some of you carry on about a 9mm being equally effective makes me wonder if any of you have actually shot a 40 at anything but paper?
Lastly, "equally effective" or "slightly more effective" doesn’t mean the bad guy died 3 hours later at the hospital from a 9mm vs being dropped on the spot by a 40, 45 or 357sig.
The (death) result may eventually be the same amongst all calibers, I want to know about immediate effectiveness.

If a round's purpose was to make the largest wound channel in gelatin, then yes, the .40 would be much better than the 9mm.

Stop criticizing the gel... Gelatin results are as good as it gets for 9mm fans... its downhill from there after considering barriers.

Gelatin provides a good baseline of what a round can do to a media that is similar in density to a human.
Add a few bones, add some clothing, add anything to impede the bullets progress and the 40, 45 & 357sig really start to shine above and beyond the 9mm.

But when you say that photo proves the .40 is far better than the 9mm, or when you say "shootability" isn't an issue because your larger Glock .40 shoots better than your smaller Kahr 9mm, you're just using ridiculous arguments.

Your either not paying attention, or not reading me correctly, or both.
I'm saying that the 40 is the way to go in pistols larger than the Kahrs - simple as that - I'm not saying that the 40 is the right pick for all pistols or shooters.

I don’t think that a Kahr PM40 is a better choice than a PM9, just the opposite in fact.
The PM40 truly is too small (for me) to happily practice with enough to be as sharp as I am with the PM9.
Move up a size to the G27, and yes.. 40 is the right choice for me in that size pistol on up.

[Theohazard]

I'm paying attention to what you're saying: you're saying the .40 is a much better round as far as terminal ballistics than the 9mm and you keep using that photo to "prove" it.

I'm not critizising the gel per se; I'm saying the fact that you're willing to use that as "proof" of the .40's huge superiority in actual gunfights is ridiculous. Just like your example of your larger Glock .40 shooting better than your smaller Kahr 9mm is also ridiculous.

I'll say this yet again: I'm not arguing the .40 is the exact same as the 9mm; I'm arguing that they're a lot closer than you think as far as their real-world effectness.

I work with a guy who is a firearms expert, trainer, and IPSC shooter who regularly trains with and is personal friends with Massad Ayoob, and he puts it best when he talks about the 9mm vs the .40 vs the .45; he says, "They all pretty much suck, so pick the one where you can put the most rounds on target accurately and as quickly as possible."

[10mmAuto]

You have provided absolutely nothing to demonstrate that 9mm, is actually, just as damaging and effective as a 40. Nada. Nothing. Zip. Zilch.

Actually I invited you to go find and compare energy levels of common loadings. I ought not have to put up something you're familiar with already. The short version is that 9mm and .40 S&W fall into the same energy range. Energy is a numerical value easily calculated and also falls into the category of data unlike your gel photo which falls into the category of interpretive conjecture.

[Dashunde]

I'm saying the fact that you're willing to use that as "proof" of the .40's huge superiority in actual gunfights is ridiculous. Just like your example of your larger Glock .40 shooting better than your smaller Kahr 9mm is also ridiculous.

I'm not saying its proof, but it sure paints a pretty clear picture of its potential compared to the others with all other things being equal.

And no, its not ridiculous, its an example of both rounds being well-matched to their pistols.
I do shoot the 40 G27 faster and more accurately than the 9mm PM9 - its mostly a factor of the larger gun, shorter trigger, and overall design, not the round in any way.
And it’s a clear example of how a pistol of certain physical size and weight (varies by user) can manage the 40 as well or better than a smaller 9mm pistol.
In other words - for me, the PM40 isnt a good match of round and pistol. Which was the OP's main question in this thread after all.

The short version is that 9mm and .40 S&W fall into the same energy range.

No. No they don’t.
You sound silly, as if you've never shot a 40.
The 40 and 45 have basically the same energy, the 40 has more in some cases.
Have you ever heard someone say that the 9mm and 45 fall into the same energy range?
Go try to sell that 9mm-has-the-same-energy nonsense to the 1911 crowd... Boo Hiss.

Energy is a numerical value easily calculated and also falls into the category of data unlike your gel photo which falls into the category of interpretive conjecture.

Good Grief... look at the photo man! The numbers you seek are to the left of the gel image.
Proof-positive your not paying attention and just waiting for your turn to talk (argue) instead of genuinely conversing.

Actually I invited you to go find and compare energy levels of common loadings...

What? I brought you a picture with numerical data along with nicely done damage photos, I invite you to find better info and bring it here smart guy.

Really..can we be done with this? I think we can all agree that the PM9 is probably right pick, instead of the PM40.

[9mmsnoopy]

I have a PM9, its a pretty sweet shooter, but i dont if the .40 would be quite as sweet. Plus if you like to shoot alot, the cheaper 9mm ammo is a plus.

[Theohazard]

I do shoot the 40 G27 faster and more accurately than the 9mm PM9 - its mostly a factor of the larger gun, shorter trigger, and overall design, not the round in any way.

Ah, you were unclear about why you were comparing the two weapons, I thought you were suggesting that caliber had something to do with your comparison.

And no, its not ridiculous, its an example of both rounds being well-matched to their pistols.

Now that you've clarified what you meant, I agree with you on this. However, most people will find each weapon easier to shoot in its 9mm version.

I'm not saying its proof, but it sure paints a pretty clear picture of its potential compared to the others with all other things being equal.

But it's an incomplete and potentially misleading picture. The real proof is in actual real-world shootings.

[10mmAuto]

You sound silly, as if you've never shot a 40.

Because there's an energy gauge on the gun?

If you meant "have you fired a .40? The increase in felt recoil and muzzle flip clearly indicate to me that there is more muzzle energy!" felt recoil and muzzle flip are the function of a lot of things and the primary determinant in them isn't energy.

No. No they don’t.

They in fact do. You should go compare some handloading manuals, a variety of manufacturers of ammunition online or even the wikipedia page on the two.

I'm sure in real life you're a perfectly nice guy, but on the internet you use willful ignorance and garden variety ignorance to craft your arguments. It's hard to have a productive discussion with someone like that.

If I had to compare it to anything else, it's hard to debate the importance of the calculus underpinnings of multilinear regression when you're a trained stastician and the person you're talking to can with difficulty do some algebra - you know some of the language and you've got an opinion, but it's an opinion based on what you don't know that you don't know..

[orionengnr]

The .40 may have a small advantage in power, but you can put more 9mm rounds in the same sized pistol...with the result being essentially a tossup...shooter's choice.

If you do some searching, the Kahr PM9 is at the ragged edge of firearm design. Most of their 9mms work...in the same sized frame, many of the .40s do not. There is a practical limit for everything.

Kahr .9mm vs Kahr .40mm

BTW, it's not .9mm...it is 9mm.
.9mm would be somewhere around .032, thirty-two thousandths of an inch. Slightly larger than the needle the nurse uses to take your blood or give you a flu shot. Probably not very effective as an anti-personnel round.

[Dashunde]

If I had to compare it to anything else, it's hard to debate the importance of the calculus underpinnings of multilinear regression when you're a trained stastician and the person you're talking to can with difficulty do some algebra - you know some of the language and you've got an opinion, but it's an opinion based on what you don't know that you don't know..

... I do however know, thats a big fat chunk of highbrow baloney.

I've understood every word and concept from you - I dont agree - therefore you proclaim yourself an elevated thinker. Blah...

It starts at post 14, think about that smart guy.

[10mmAuto]

I've understood every word and concept from you - I dont agree - therefore you proclaim yourself an elevated thinker. Blah...

No, but an elevated thinker relative to you, as revealed by your incorrect citation of facts as well as erroneous thought on the topic and tangentially related subjects.

For example, your insinuation that you can accurately gauge energy levels of .40 relative to 9mm by the feel of shooting it and therefor conclude .40 is substantially more powerful than 9mm because it has much more muzzle flip/recoil is the most asinine thing I've heard about firearms recently - and I'm in the military, where you hear brilliant stuff from 11B junior enlisted like .50BMG near misses tear limbs off. Telling me they're not in the same energy range when it is well documented on the internet that they are was just.... -_-.

If you're curious how I came to the conclusion I initially touched on, PM but when you consider what I outlined in the body of my post it's clear you're willfully ignorant of the topic at hand and also not well informed on small arms.