Ammo advancements like the new seismic ammo 185gr 9mm loading really pushes close to common 40s&w.

That said using shell shock technology casings could net a gain with 40s&w due to better taking the chamber pressures and in some cases actually having more case volume

One thing I have noticed is that quite a few 40 loads are downloaded or slow unlike 9mm being loaded quite hot quite commonly

I contribute that to 40s&w already pushing razors edge of pressure at common saami loads and 9mm typically has more headroom before hitting truly dangerous pressures

That's a psychological stop, where the attacker *chooses* to stop the attack even though capable of continuing. In instances like that, caliber/bullet used is moot (unless you can provide hard data proving how/why a particular caliber/bullet is significantly more effective in causing a psychological stop).

I agree it's rare for an attacker to continue to fight after being hit (hence my 'aggressive and determined attacker' reference), but when it does happen, all handguns underperform, even the mighty .45.
Ex: https://www.policeone.com/police-heroes/articles/why-one-cop-carries-145-rounds-of-ammo-on-the-job-clGBbLYpnqqHxwMq/

Tomac

No one is arguing the difference in wound channels. What's important is the ability for a given caliber/bullet to stop a determined and aggressive attacker before he can inflict serious/lethal damage. No std 9mm/.40/.45/.357/10mm handgun can *reliably* accomplish that.

Tomac

Most people who say they shoot a 40 well don’t. Those who do shoot a 40 well will shoot a 9 better.

Thin skinned medium animals. Yes, 9mm is fine.

40 makes sense if large bears are a concern wilth appropriate ammo selection.

Maybe. false. I disagree.

That’s completely false. There are 9mm loads that penetrate 60 inches. Bears dint like being shot and break off an attack over 95% of the time after being shot with any handgun

I find the bare and clothed gel results more relevant than the sheet metal results.

45 has less muzzle flip than .40SW. I always shot 9 and 45 better than 40.

Not suppressive fire. Rather poking holes in a person fast until you get a CNS stoppage. 17 rounds in a mag gives more chances than 15 rounds in a mag does to obtain that stoppage prior to a emergency reload.

I'm in agreement with StevenH.

Also, I shoot 9mm better than .40, so that alone is reason enough for me.

With organic gel I agree. I liked that sheet metal test as it was comparing hardcast bullets. Denim or 4 layer clothing is wasted on hardcast.

I also like sheet metal tests because of the amount of time I spend around vehicles.

I think the difference between 15-17 is largely academic without any differences in practically. Without any real world events that 15 rounds failed and 17 succeeded that I know of.

I do remember a MOH citation that references a Marine with an empty 1911 in the south Pacific surrounded by 7 dead japs, bayonetted to a tree iirc.

What I’ve noticed, watching gunfight videos and speaking to the winners of gunfights, is they usually end when one or both parties shoots to slide lock. 9mm gives me two more tries for that CNS hit

Could you post some of those videos?

I once shot an old, heavy college chemistry book with 9mm blazer 115 FMJ from a 4" barrel S&W, made it about 2/3rds of the way through.

A Glock 22 using .40 165 grain blazer FMJ (4.5 barrel) went right through.

The 9 was probably pushing around 320 ft lbs, the .40 maybe 400.

It made an impression on me.

As someone said before, shoot something that you like and good with it.

I have Glock 30, 21Sf, 21 gen 4, 41.  All have been converted to shoot 10mm, using barrel conversion, 10mm mag, and 10mm extractor.  The benefit of this setup is that I can also shoot 40 s&w out of them too.

I have noticed that I can shoot very accurately with any of these pistols with above setup, and can routinely put 50 rds in black circle ( fist size) at 21 feet.  The 40 cal in G30/10 is a joy to shoot!

So far, I have no desire to shoot any of my 9mm pistols at all.

I will fall upon the relevantcy of this test when I am preparing to defend myself from chemistry textbooks.

That's what I was thinking too. LOL

Penetration in hard objects is determined by energy and bullet construction.  Smaller diameter projectiles with the same energy and bullet construction will penetrate deeper than larger diameter bullets.   An example friend had an old burned out car we tested a bunch of ammo on.   A 115 grain 9 MM W-W +P+ at 1300 FPS would penetrate better than a 125 grain 357 magnum semi jacketed hollow point at about 1350-1400 FPS.   Bullet construction of the lead tip bullet reduced penetration in steel.   The W-W 145 grain Silvertip bullet had good energy and jacket all the way into the nose like the semi auto bullet and was a very good penetrating bullet.

Change the bullet construction or velocity can drastically affect penetration.  More velocity on lightly constructed bullets reduces penetration. Laminated auto glass is very destructive on many cup and core bullets and is a good test to perform when comparing different bullet designs.  Shoot some laminated auto glass with 22 rimfire copper plated round nose.  Surprisingly  the rimfire bullets do pretty good job on auto glass because of the balance between bullet construction, velocity and energy.

It’s an anecdotal example of what I consider to be a good example of the relative power of two cartridges. I can’t help but think that it would make a difference hitting a rib with the .40 vs the 9

I once shot a 400 page phone book with 22lr that penetrated about 1/4 the way through (100 pages)
Then I shot with a 22magnum. 22mag blew through the whole thing and shot confetti out the back about 25 feet. Not sure if this is relevant or not

I shot a stack of magazines (the paper kind) with a 6.5mm Creedmoor and it only made it about 8" in. A .357 Magnum got about 7" under the same conditions; My 9mm made it out the back (about 14") and kept going.

Let's see if anybody can figure out the first question they SHOULD be asking every time somebody posts nonsensical "tests" like these, and discover the factor that's far more important than caliber in selecting a round for defensive use.

If a ribcage were in any way the ballistic analog of a dry book, that would be relevant.

As they are not, it’s not relevant.

It's interesting for sure, but I'd chalk that up to large differences in velocity and bullet construction since I'd guess your .22 WMR had a copper jacket

The .40 uses a larger diameter, heavier projectile traveling at similar speeds to the 9mm.

There is no way in hell that the 9mm ( in general) has the same stopping power as the .40.

The primary reasons for the switch back to the 9 is slight increase in magazine capacity and less recoil.

More folks can shoot well with the 9mm than the .40.

The general consensus among LE agencies (not just FBI, but other large PD's) after analyzing decades of Officer Involved Shooting Incidents, is that there is no noticeable difference in the way 9mm and .40 perform in terms of leading to a successful outcome for officers involved. Basically, the other factors that tie into a shooting far overshadow the small difference of .05" in diameter between two projectiles of otherwise similar construction.

Many departments/agencies/units have made the switch one way or another between them. Zero have reported any statistical difference in outcomes. You've controlled for every other variable. It's the same officers (so same level of training, experience, etc.) patrolling the same area in the same way they were before, only the cartridges are different. If one were measurably better than the other we'd have those measurements by this point. 9mm hasn't given better performance, but it's not worse either. It's the same, so why go with the caliber that has less capacity, more wear and tear on the weapon, higher ammo costs, and is harder to shoot well?

Care to define "stopping power" and provide hard evidence proving the .40 is significantly more effective than 9mm?

Tomac

I don't think I've seen a hitch hiker in 10 years! lol

The ability to stop a threat quickly.

I'm not sure if the .40 is "significantly" more effective than the 9mm.

I am sure of the fact that the .40 pokes a bigger hole, has more penetration and as a result of those facts; it has to ( in general) stop better.

To me, that's common sense.

Reality does not support your "facts", nor do the last 2 decades of analyzed OIS incidents. They all perform so similarly in effectiveness that it's immeasurable. If there was some difference in effectiveness at incapacitating an attacker between high-quality .40 duty loads and high-quality 9mm duty loads, we would've seen it by now in the tens of thousands of officer involved shootings over the last 20+ years.

Feelings are not facts.

If the .40 isn't significantly more effective than 9mm, why your previous "no way in hell" statement?

All handguns are relatively poor 'stoppers' regardless of caliber or bullet used. Barring a hit to the CNS, the only way to stop a determined and aggressive BG is shutting down the brain via oxygen deprivation caused by blood loss. Even a solid hit to the heart can leave 10+ seconds worth of oxygen in the brain, plenty of time for the BG to inflict serious/lethal injury. Will the slightly greater diameter of the .40 significantly increase blood loss and decrease time to incapacitation?

Shot placement and sufficient penetration are paramount, all else is secondary. All handguns underperform, some underperform worse than others.
Larger calibers don't guarantee reliable terminal performance: https://www.policeone.com/police-heroes/articles/why-one-cop-carries-145-rounds-of-ammo-on-the-job-clGBbLYpnqqHxwMq/

Tomac

How many more “Stopping Powers” do you figure a .40 has than a 9mm?

I have no idea

I agree shot placement is key.

I carry a G19 when I CCW.  Not knocking the 9mm at all. It just seems logical to me that the .40 would have a greater chance of stopping a threat.( Because it pokes a bigger hole)

There was a reason LE went to .40 in the first place.

Edited to add

I have relatives who are in law enforcement. In a nutshell, the consensus amongst them and their co-workers is that the .40 is a better stopper than the 9mm. Just a few cops opinion but worth mentioning.

Slug design has come a long, long way in the decades since .40 entered the market.

How many of these LEOs have been involved with a shooting with either caliber, let alone both under similar circumstances with sufficient frequency to have an opinion on the matter worth listening to?

Despite TV, it’s not terribly common for your average LEO to be involved in a duty related shooting.

2 slightly smaller holes has a lot more wounding potential than one slightly larger hole. The diameter difference between a .358 bullet and a .400 bullet is not nearly enough to trump the ability to fire more rounds more quickly and accurately.

Shot placement is king
Shot repeatability is queen
Shot caliber is the court fool.

All good points.

The only cop I know who was involved in a shooting was a guy who used to work with my BIL.

He used a G22 and put the perp down quick; according to what I was told.

Agreed.

That's why 9mm made a comeback.

Yes, and why you won’t be able to trade a 9mm handgun in for a decent price when .380 takes over.  It’s far more controllable, with much less blast and recoil than the 9mm.  It allows for a more compact design, lighter weapon weights at the same capacity and far faster follow up shots which means:  more rounds of .380 on target than 9mm, especially when used by smaller shooters.  As it’s loads have  evolved to produce results in gelatin that narrow the gap to a small percentage, its dominance increases.

I know this post was made in jest, but going from .40 to 9 doesn't indicate a logical conclusion of going from 9mm to .380. There are currently no duty-worthy .380 loads that can both expand reliably and penetrate 12"-18" reliably in tissue or a strongly correlated medium like 10% ballistics ordnance gelatin, particularly after passing through barriers. Whereas 9mm does it just as well as .40 and even better through certain specific barriers (metal and wood). Being that 9mm and .380 are the same diameter in both projectile and (roughly) case, you can't stuff more .380's in a magazine of comparable size of 9mm, whereas you can with 9mm compared to .40.

.380 pistols tend to be snappy either by virtue of it's typical direct blowback format and/or otherwise being too small and light to shoot any better than a 9mm. Anecdotally most find .380 to be snappier and harder to control than 9mm in any format. So it has no capacity advantage, no recoil advantage, the ammo is more expensive, and it doesn't meet minimum terminal ballistics requirements. There's really no comparison between 9mm vs .40 and .380 vs 9mm.

Maybe one day there will be .380 loads that perform adequately, but even then it wouldn't be able to offer the same advantages over 9mm that 9mm has over .40. Plus, and I could be proven wrong in the future, but I just don't think there's enough lead and powder to work with within the .380's limited dimensions to meet said minimum requirements.

It's difficult to compare 9mm to .380 because pretty much every .380 ammo test you're going to find will have used a 2.75" barrel or similar.

This appears to be what you're doing given your "snappy" comment. Yeah, the Ruger LCP is more snappy than a G19.....now what if you shot a G19 chambered in .380?

I'm not saying the .380 will ever equal the 9mm- it won't- but it's intellectually dishonest to compare the traits of a 9mm shot out of something like a G19/17, to the .380 shot out of something like a Ruger LCP.

The same goes for your comment about the ammo. There are some loads in .380 that come close to and even meet the 12-18" penatration standards from guns like the Ruger LCP. Now how would it look if the .380 was shot from a 4-4.5" barrel like the 9mm? I'll bet the difference between the 9mm and .380 you're describing gets a lot closer.

I think a PPKS has close to a 3.5" barrel and, to me... my PP365 is smaller, lighter, easier and more enjoyable to shoot, is at least as accurate with 124 & 147 gr HST's / Gold Dot's etc

By that same logic, .22lr should fit pretty well, and anything else does not matter..... !?!?  No one should need 44magnum or anything bigger?

I'm trying to figure out whether this statement better fits the reductio ad absurdum or the straw man logical fallacy. Perhaps both? Something else?

Both...

I get what you're saying, but actually, I was thinking about a small 9mm vs a small .380, and a large 9mm vs a large .380. In my experience, the Beretta Cheetah (which is similar in size to a G19) has more "snap" to it than a comparable 9mm. I suspect this is because that the most practical method of operation for a larger .380 is blowback rather than locked breech due to the lower pressures. Granted, this is partially subjective, but I don't find it any easier to shoot than a comparable-sized 9mm.

Likewise, when shooting the ultra-compact 9mms next to .380s, I also found the 9mm to be easier to shoot with more of a push than a snap. (I'm fortunate enough to work at a gun shop where I can take used guns out to the range.)

I've never seen a .380 ACP load that reliably and consistently passes all of the FBI protocol gel tests, especially tests including barriers (4 layer denim, wood, sheet metal, and especially auto glass). While some don't see the merit in having a round that can penetrate such barriers, I do think it's important; when I look around, I see a lot of barriers that might have to be passed through in a self defense situation. Even with no hard barriers, having to break through bone or go through the arm before reaching the body makes the best .380 load a lot less likely to penetrate to vital organs, based off the few professionally-conducted LE tests of .380 ACP. If I were going to carry a .380, I'd most certainly stick with FMJ to ensure better penetration, and I don't see a point in that when 9mm can penetrate more than adequately with good expanding loads and be less snappy in comparable sized platforms to boot.

I'm not necessarily convinced that a longer barreled .380 will have better penetration than a shorter one. Most expanding loads are designed to operate within a specific operating window of velocity. If there's a barrel length that is significantly longer enough to change the performance of a .380, generally that would not be for the better and you'd see either over-expansion and underpenetration, or the petals peel back to the core and have a less-than-ideal expanded diameter.

All in all these factors lead one to believe that the .380's bullet weights and velocities will not lead to reliable penetration to adequate depths in at least certain barriers when expanded, and many times through only heavy clothing (the stage of gel test which has been most heavily correlated with how a bullet behaves in a human body). At the same time, good 9mm loads like the Hornady Critical Duty, Winchester Bonded, Speer Gold Dot 147gr, and others have shown to be able to expand and penetrate adequately after passing through all the normal barriers.

Yeah, I see what you're saying. I will sometimes carry my Ruger LCP in my pocket, but in all honestly I don't really like the gun. It's loaded with the Lehigh Defense load which is actually a pretty good load for .380 and does as good as one could expect the .380 to do- even through barriers- but obviously won't match 9mm performance. My issues is more with the platform. The LCP for me is a legit 7 yards max gun, and you won't see me chasing down any active shooters with it. The recoil is also pretty stout which you've mentioned.

I bought an M&P Shield not all that long ago and I love it. Since I work from home there are very few times I have to carry the LCP instead of the Shield, and most of the time it's more "grab and go" convenience than anything. The Shield is loaded with 147 grain HST.

You're describing exactly the opposite of every other recoil experience I've had or heard with these guns

My Cheetah had almost .22 LR levels of recoil, way less than the softest 9mm pistols I've ever shot. The front sight never left an index card at ten yards during recoil. Tiny 9mm pistols like a Kahr have quite a sharp snap to them, nothing at all akin to the sort of recoil I've ever had described as a "push". There are also locked-breech designs that make the recoil of either cartridge easier on the hands; try shooting a Glock 42 next to a 43 for the best direct comparison I can think of. Nearly identical guns, both tilt-barrel, one in .380 and one in 9x19mm. I've always found the 42 to be quite tame and a very fast shooter.

The 9mm crowd always comes up with excuses.  There's no way that you're going to put 2x 9mm on target for every 1x .40.  Sure the split times could be slightly better with 9mm, but at best it would be like 11x 9mm on target for every 10x .40.  The .40 does recoil slightly more, but it hits harder and expands bigger, and if you're good enough to shoot 9mm fast and accurately, you can do the same with .40.   It always seems that the 9mm crowd thinks that anything less than 9mm is wholly inadequate and anything bigger is just too much recoil with zero gain in ballistics.

If they designed a 380 round that would reliably expand and penetrate from a longer barrel, say a 4" barrel, and something like a longer, higher capacity G42 came out, would 9mm guys flock to it because it would be very soft shooting.  I have a G42 that is super easy to shoot, a longer barrel and a thicker grip to accommodate more rounds would be great.  Many 9mm guys think the 357 SIG is pointless btw, even though it performs better.

Yes. Selecting the round that is easiest to shoot accurately/reliably, that meets the desired terminal performance criteria, is called making a good informed decision. The reason nobody carries .380 is because it underperforms. The reason people carry 9mm is because it is the lightest, highest-capacity, easiest-shooting caliber that not only meets the terminal performance requirements, but does so on par with the larger calibers without giving up the inherent advantages of a smaller/lighter cartridge. Bigger makes people feel better, but feelings are irrational.

I really like the 357 SIG round, but hardly ever see it compared to either 9 or 40. Although I've heard some say It is no better than a 9, I disagree. It doesn't recoil much different than a 9, but with ammo like Underwoods 125 gr. GD going 1500fps out of a G32 it is nothing to scoff at. That's 357 Mag territory with a great bonded bullet. In my tests on an old car the 357 almost always penetrates better than 9, for whatever that's worth. Probably not much to a non LEO. In the end, as has been said repeatedly, shot placement is key.

I'm also a big fan of .357 SIG, and IIRC it came out as the top performer at shooting through windshields. I used to keep one in the center console specifically for defense from within the vehicle, again because it's the lightest and most efficient way to meet the performance requirements. A .44 Mag would've been at least as good in terminal performance, but at a cost.