.40 vs 10mm for CCW/Self-Defense (Against Humans)

[mavracer]

I carefully explained the detriment.

Some organs stretch and return. Some organs do not stretch, they tear instead which does cause wounding. Here's some more information on the topic.

Gunshot wounds in parenchymatous organs: the morphology mainly depends on the physical properties of the affected tissues*

In contrast to gunshot wounds in skin and bone, the medico-legal literature pays little attention to the appearance of bullet penetration sites in abdominal organs. It was only in 1983 that Metter and Schulz published an article entitled “Morphological ...

www.ncbi.nlm.nih.gov

"According to their observations, the organs in question showed stellate tears at the bullet penetration sites resembling skin wounds from contact shots to body regions having a bony support. The study presented simulated the real conditions by means of test shots to composite models consisting of porcine organs embedded in ballistic gelatin. The ammunition used was pistol cartridges 9 mm Luger with full metal jacket round nose bullets. The shots were video-documented with a high-speed camera in order to record the bullet’s travel through the target. In addition, the composite models fired at underwent CT examinations followed by a macroscopic assessment of the organs. The study confirmed the findings of Metter and Schulz with regard to the star-like appearance of gunshot wounds in the liver and spleen. Likewise, the kidney showed radiating tears originating from the bullet path, whereas the wound track in pulmonary tissue was tube-shaped and lacked additional cracks. The varying wound patterns in parenchymatous organs can reasonably be explained as a consequence of the respective viscoelastic tissue properties."

"Ruptures radiating from the bullet path indicate that the target material was temporarily exposed to tensile stress beyond the limit of plasticity. This applies to proportionally dense organs such as the liver, spleen, and kidney, but far less to the air-containing and highly elastic lung."

The article contains additional information, including pictures of the damage to tested organs.

That is incorrect --as I've explained.

The ATK engineers correctly note that at rifle velocities, even the elastic tissue can tear and be wounded. They are wrong about temporary cavity not causing any wounding at all with handgun rounds because they don't take into account that not all organ tissue is elastic. If you try to stretch a kidney, it will tear, not stretch. Same with a spleen, same with a liver. You can verify this if you really care about the topic. The issue is that if those inelastic organ are not close enough to the bullet path to be affected by the temporary stretch cavity, then the temporary stretch cavity will not have any wounding effect at all. So it's very true to say that temporary cavity is not a reliable wounding effect in handguns, but it's not correct to say that it can't ever have any wounding effect at all. If you go back to the original source of this information, you will see that it most often makes the statement that "Temporary cavity has no reliable wounding effect in elastic body tissues..." but the word "reliable" is often dropped when the quote is restated. Here's an example.

The myth of the temporary wound cavity - Gun Nuts Media

The tissue disruption caused by a handgun bullet is limited to two mechanisms. The first, or crush mechanism is the hole that the bullet makes passing through the tissue. The second, or stretch mechanism is the temporary wound cavity formed by the tissue being driven outward in a radial...

www.gunnuts.net

"Temporary cavity has no reliable wounding effect in elastic body tissues" is the actual quote but the article's author then restates that quote as:
"The only wound mechanic of a pistol bullet is the permanent crush cavity, which is the actual path of tissue destroyed by the bullet." Which is not the same thing at all as noting that Temporary cavity is an unreliable wounding effect.

In addition to that the whole premise of defining permanent wound channel and temporary wound channel attempts to define a line that doesn't exist in real tissue.
If the definition held up a hard cast round nose would have the same wound channel as a SWC or WFN, which had been well known to not be the case decades before HWFE was published.

in even a large 10" human torso

Humans have these things called arms which often in SD scenarios are in front of the torso, which is why HWFE says 12" Minimum and 16" would be preferred.
Another snippet that often gets ignored.

Academic minutia.

You can do that all the way from 25ACP to 500 S&W magnum.

 

[LookAtYou]

The biggest issue with the FBI not going with 10mm wasn't recoil, the load they used was effectively a typical .40 S&W level loading, but rather the size of the gun itself. That's pretty much the reason .40 even exists at all, as it's able to give good performance from a 9mm sized handgun.

I have and shoot both .40 and 10mm and I'll say that if I had to choose just one, I'd pick .40 every time. That's not to say that I don't like 10mm, I have some nice guns chambered in the 10mm, but for carry purposes and really also for home defense, I always felt the .40 was essentially the perfect option. You do get more power with 10mm, but that comes at the cost of a bigger gun. While on the topic of power, I have two points. One, if I really need more power than .40 S&W, I'll likely grab the .44 Mag Ruger or S&W, although the .40 will work for deer sized game. Second, and this point is somewhat controversial, is that while the 10mm is more powerful, I don't feel that it's "far more" powerful. I say this because I've ran warm handloads through both and realistically the 10mm has about a 100 fps advantage over the .40, give or take ~25 fps depending on a heavy bullet vs. light bullet.

More is more, no doubt, but how much difference does that make in the long run? The 10mm is a very good and versatile option, but it gets praise while the .40 gets scorn. That doesn't make sense to me, as people often (in this very thread) want a 10mm sized G23, yet if one did exist, it wouldn't be appreciably better than the G23 already is. I can run a 180gr @ 1350 fps from a 5" 10mm and guess what, it'll work in the woods. But guess what else? So will factory level .40 S&W loads. If I can load a 180gr @ 1250 fps from a 5" .40 S&W, I guess I have to wonder what the 10mm really gives me, you know. It's more powerful but is it really that much more capable? But okay, I don't want to step on too many toes here so I'll quiet down a bit. I do get why the 10mm is popular, and that's because you can buy warmly loaded 10mm and have it shipped to your door, so really you don't need to handload to get a certain level of performance from your gun (whereas you do with .40)...basically it's just more convenient.

My 10mm handguns:

Two Colt Delta Elites
View attachment 1172497

Six-inch and five-inch Springfield Armory TRP Operators
View attachment 1172498

A Glock G40 MOS when I want more capacity
View attachment 1172499

And this is another reason why I personally like .40...


23 shots in a Glock 23!
(22+1, Glock Factory 22rd mag)
No 10mm is gonna give you this overall capacity/firepower, reliably at least.

 

[JR24]

And this is another reason why I personally like .40...

View attachment 1180333
23 shots in a Glock 23!
(22+1, Glock Factory 22rd mag)
No 10mm is gonna give you this overall capacity/firepower, reliably at least.

I’ve generally heard good things about the KRISS mag extensions for the 10mm. Gets you to 33 I think.

 

[vindag]

The biggest issue with the FBI not going with 10mm wasn't recoil, the load they used was effectively a typical .40 S&W level loading, but rather the size of the gun itself. That's pretty much the reason .40 even exists at all, as it's able to give good performance from a 9mm sized handgun.

I have and shoot both .40 and 10mm and I'll say that if I had to choose just one, I'd pick .40 every time. That's not to say that I don't like 10mm, I have some nice guns chambered in the 10mm, but for carry purposes and really also for home defense, I always felt the .40 was essentially the perfect option. You do get more power with 10mm, but that comes at the cost of a bigger gun. While on the topic of power, I have two points. One, if I really need more power than .40 S&W, I'll likely grab the .44 Mag Ruger or S&W, although the .40 will work for deer sized game. Second, and this point is somewhat controversial, is that while the 10mm is more powerful, I don't feel that it's "far more" powerful. I say this because I've ran warm handloads through both and realistically the 10mm has about a 100 fps advantage over the .40, give or take ~25 fps depending on a heavy bullet vs. light bullet.

More is more, no doubt, but how much difference does that make in the long run? The 10mm is a very good and versatile option, but it gets praise while the .40 gets scorn. That doesn't make sense to me, as people often (in this very thread) want a 10mm sized G23, yet if one did exist, it wouldn't be appreciably better than the G23 already is. I can run a 180gr @ 1350 fps from a 5" 10mm and guess what, it'll work in the woods. But guess what else? So will factory level .40 S&W loads. If I can load a 180gr @ 1250 fps from a 5" .40 S&W, I guess I have to wonder what the 10mm really gives me, you know. It's more powerful but is it really that much more capable? But okay, I don't want to step on too many toes here so I'll quiet down a bit. I do get why the 10mm is popular, and that's because you can buy warmly loaded 10mm and have it shipped to your door, so really you don't need to handload to get a certain level of performance from your gun (whereas you do with .40)...basically it's just more convenient.

In California we are limited with mag capacity, and handgun selection. I would rather have 10+1 in .40 165gr, than 10+1 in 9mm. So, my carry is Glock 27 gen 3, and home defense is original Springfield XD40 Service 4 inch, as these are both on the California Handgun Roster. Both of these guns are the exact same size gun, as their 9mm editions. I also have a Glock 30 gen 3 .45 10+1, but as you so perfectly stated with the 10mm, the size of the gun is larger. With my small hands the Glock 30 grip feels fat, and uncomfortable. I actually shoot it better than the other 2, which just goes to show you a gun doesn't need to be comfortable to shoot well. It's not like a pair of shoes. That said I still only use it for occasional range use, as it sits mostly in the safe.

 

[MikeInOr]

10mm: A larger and faster round, with similar bullet weight (sometimes heavier if 200gr+ ammo) compared to .40. In average ccw sized guns (say 4" barrel or less), the ballistics can be strikingly similar compared to .40, but generally more penetration and expansion. Also, more RECOIL, and potentially MUZZLE FLASH in general. This means harder to shoot, slower follow-up shots, more chance of flinching, higher risk of a complete miss, etc., compared to .40.

Maybe for a newb the 10mm is harder to shoot with more chance of flinching/missing but for the well practiced, like many members of this forum, this simply isn't true.

I don't own a 10mm but I have shot plenty of them. I don't make my gun choices on commonly recited misconceptions like many newbs are apt to. Your thesis is more relevant to gun rags which are aimed at selling stuff to the uninformed masses that don't know any better... it is a lot less pertinent to those of us on this forum that have been around guns for a good while and have learned to ignore such diatribe.

 

[LookAtYou]

I'd take a 10 mm all day long. Ammo selection helps mitigate some of the concerns. You can get soft shooting, less penetrating 10 mm ammo for dangerous 2 legged critters or heavy hitting, more penetrating 10 mm ammo for larger, dangerous 4 legged critters.

Basically, a 10 mm can do what a .40 S&W can do, but not the other way around.

Focusing on your first paragraph, you're basically agreeing with what I, and some previous posters, have said. Wanna semi-auto/"high capacity" handgun round for hunting animals? 10mm is pretty viable. Want to defend yourself against other people, .40 (or 9mm or .45 or whatever), due to multiple reasons, is better, for MOST.

As soon as you start decreasing normal 10mm load power levels, and the more you do it, the more one can argue you might as well have just use a .40

 

[LookAtYou]

Well, since the 10mm Glock 20 is the Mil-issue sidearm of Denmark’s Sirius Sledge Patrol soldiers for defensive use against Polar bear attacks, it should suffice against 2-legged predators.

A 10mm 200grn slug @ 1200fps …. all day long.

The .40S&W is for Boomer grannies with arthritis wrists.

Would you be able to reasonably and consistently CC a G20?

 

[LookAtYou]

I don't have a 10mm handgun, but I'll get one eventually. It will probably be a range toy.

IMO, 40 caliber is plenty adequate for SD. I wouldn't prefer more recoil and muzzle blast.

Similarly, I used to load 357's in my HD revolver. Then one night I had to fire a shot with no hearing protection. Since then it's been loaded with 38's.

Care to share what occured that fateful night, that led up to the shot being let off?

 

[Tallball]

@LookAtYou It's okay to share the details of "that fateful night".

The woman next door was stupid and would let her dog run around loose (in the middle of a city of over 100,000) and chase bicyclists. One night a really wasted bicyclist took great offense to this, chased her dog to the front door, and tried to force his way in.

I woke up to him screaming and cursing outside. I stepped out with my 357 and saw her trying to hold the door shut and him gradually forcing it open. He was a big muscular young guy with no shirt.

I yelled at him, but he didn't respond. I didn't want to get beaten to death by him or murder him, so I shot the mud at the base of a tree. That got his attention (and everyone else on the block). I loudly and deafly shouted that the next one was for him. He fled the scene.

 

[S.Crockett]

Would you be able to reasonably and consistently CC a G20?

Yes & yes, especially in the cooler/colder months with a covering garment.

In the hot “t-shirt” weather my G29 disappears IWB.

 

[crestoncowboy]

I suppose it depends on who you're talking to. Glock never has offered their .45 Auto or 10mm guns in a Compact model. However, the Subcompact G29 and G30 approximate the size of the G19/G23.

You aren't going to get the grip dimension of the G19/G23 with a .45 Auto or 10mm as the rounds are too long to fit that grip size. Of course, that's why Glock made the G23 (.40 S&W, essentially 10mm short) and the G38 (.45 GAP, essentially .45 Auto short).

Glock calling the 29 "sub" compact was a mistake (lie) in the first place. They made the 17 first. Full size. Then the 19 compact. So when they made the smaller 26 "sub" compact was correct. There was never a "compact" so you can't have a "sub" and the 29 is bigger than the 26/27 .

I will carry a Glock 20 if I'm in polar bear or grizzly country. I was, for a little while in a previous lifetime, issued a Glock 23. Not really ergonomic, a bit snappy in the recoil department, barely adequate accuracy. Reliable, though.

If I knew I was running into a bear I would not carry any 10mm. Ive hunted with 10mm for 20 years in bear woods though. Snaller black bear. Back before it was cool. While 10mm was still "dead"

Well, since the 10mm Glock 20 is the Mil-issue sidearm of Denmark’s Sirius Sledge Patrol soldiers for defensive use against Polar bear attacks, it should suffice against 2-legged predators.

A 10mm 200grn slug @ 1200fps …. all day long.

The .40S&W is for Boomer grannies with arthritis wrists.

Ive heard and read all about that for 20 years since I myself started using 10mm after our county issued the Glock 20. I wonder how many polar bear they have ever shot. And they also still carry a ww1 Enfield in 30-06.....this tells me that either nobody cares about the Sirius sledge patrol or they basically carry guns for show. If I sign up to be a soldier and they issue me a ww1 bolt action rifle I'm not feeling like I'm a valued member of the forces. Lol. They also carried a p210 at one time.

I guarantee that if polar bear attack were actually an issue the patrol would have a 12 guage with slugs and a better (post 1930s) rifle.

There is just no world where a military patrol who ACTUALLY had to worry about bear attacks or people in 2023 would carry a 10mm when there are 44 magnum/500 smith/480 ruger etc etc are available. Nor do any serious (not sirius) military unit carry a ww1 Enfield. There are just better options. Even the crappiest poor third world military have AK and even poor police units have m1 carbine and such at this point. They also have pack dogs on a sled so bear most likely shy away from it anyhow.

Maybe for a newb the 10mm is harder to shoot with more chance of flinching/missing but for the well practiced, like many members of this forum, this simply isn't true.

I don't own a 10mm but I have shot plenty of them. I don't make my gun choices on commonly recited misconceptions like many newbs are apt to. Your thesis is more relevant to gun rags which are aimed at selling stuff to the uninformed masses that don't know any better... it is a lot less pertinent to those of us on this forum that have been around guns for a good while and have learned to ignore such diatribe.

The 10 will have slower split times for anyone. Ive shot against a timer for years and ive shot 10mm in everything from bren 10 to my Glocks 20 and 29 to my kimber and delta and 220. More power means a bit more time to get on target after the first round.

Is it enough to matter? Idk. Doubtful. Do you need the extra 150 fps from 10mm.....also doubtful.

Would you be able to reasonably and consistently CC a G20?

Sure. I can carry my 20 IWB as easy as a 23 or even a 27 so long as the grip sticking back isn't an issue. In even a light jacket its not an issue. I despise the Glock 29. I bought mine right after my 20. I don't think it will ever be used again. I've said for 10 years it's a "worst of all worlds" gun. Too big to readily hide like a 27 in a tank top and shorts.... and if you are dressed like an Eskimo you may as well have the extra recoil mitigation/ capacity/ sight radius of the 20. And ive also said the same of the 19/23 vs the 26/27 and 17/22. On paper they look great but in practice I feel they took the flaws from both of the other sizes and gave up all the pros. Lol. But I know others love them so to each their own. .


Im a 10mm fan. Have been a vocal supporter on here for near 20 year. Ive killed well up in the double digits of whitetail with 10mm. Killed many beef and a few wounded Horse too. Ive probably seen as much REAL WORLD 10MM internal damage as anyone on here (and probably posted as much about it). Its a fine round. But I do feel the 40 is a better ccw or SD gun around a crowd. One could easily carry 40 in their 10mm though if chosen. Ive fired 10s of thousands of 40 through a 10 with nary an issue. Ive had 10mm go through 250 lb deer on several occasion so I guarantee you that it "can" overpenetrate. Thats 200 GR xtp and 180 hard cast. The xtp is an excellent hunting round. It penetrates deep and is a pretty sorry expander. Lol. I look at it as barely more expanding than a hard cast and barely if any less penetrating. Lol. Ive seen them crush through a rib on both sides, through the vitals and out. I wouldn't want to use it for SD when a 40 may be less likely.

10 or 40....either one is fine. Split times will be slower with 10. Barely. Power is higher with the 10. Barely.

 

[Buzznrose]

deleted…

 

[S.Crockett]

Well, since the 10mm Glock 20 is the Mil-issue sidearm of Denmark’s Sirius Sledge Patrol soldiers for defensive use against Polar bear attacks, it should suffice against 2-legged predators.

A 10mm 200grn slug @ 1200fps …. all day long.

The .40S&W is for Boomer grannies with arthritis wrists.

Crestoncowboy came along and unburdened himself with: Ive heard and read all about that for 20 years since I myself started using 10mm after our county issued the Glock 20. I wonder how many polar bear they have ever shot.

Several over the years. Sudden incidents involving unexpected charges.

And they also still carry a ww1 Enfield in 30-06.....this tells me that either nobody cares about the Sirius sledge patrol or they basically carry guns for show. If I sign up to be a soldier and they issue me a ww1 bolt action rifle I'm not feeling like I'm a valued member of the forces.

You have no idea what you’re talking about, but nice trolling anyway. Here’s a hint: a 30-06 bolt rifle loaded with 220grn ammo has stopped plenty of Grizzly and Brown bears over the decades. But remember, the Sledge Patrol soldiers aren’t assigned to the arctic regions of Greenland to hunt polar bears.

They also carried a p210 at one time.

They ditched that for the 10mm Glock 20.

I guarantee that if polar bear attack were actually an issue the patrol would have a 12 guage with slugs and a better (post 1930s) rifle.

Well, you’d be wrong.

There is just no world where a military patrol who ACTUALLY had to worry about bear attacks or people in 2023 would carry a 10mm when there are 44 magnum/500 smith/480 ruger etc etc are available. Nor do any serious (not sirius) military unit carry a ww1 Enfield. There are just better options. Even the crappiest poor third world military have AK and even poor police units have m1 carbine and such at this point. They also have pack dogs on a sled so bear most likely shy away from it anyhow.

So they should replace a proven, 15+1 semi-auto bear-stopper with a low-capacity (5- or 6-shot) boat anchor?

LOL! … So much tragic fail in this post.

 

[crestoncowboy]

Several over the years. Sudden incidents involving unexpected charges.


You have no idea what you’re talking about, but nice trolling anyway. Here’s a hint: a 30-06 bolt rifle loaded with 220grn ammo has stopped plenty of Grizzly and Brown bears over the decades. But remember, the Sledge Patrol soldiers aren’t assigned to the arctic regions of Greenland to hunt polar bears.


They ditched that for the 10mm Glock 20.


Well, you’d be wrong.


So they should replace a proven, 15+1 semi-auto bear-stopper with a low-capacity (5- or 6-shot) boat anchor?

LOL! … So much tragic fail in this post.

Lol is right

 

[S.Crockett]

 

[LookAtYou]

A lot of people did, that's why the FBI was loading their 10mm down to that level in the first place--a decision that led to the development of the .40S&W and made it viable to begin with. Also why .40S&W became so popular. I don't think many people would argue that the .40S&W is not an effective LE/SD cartridge.

Just pointing out none of that is the same thing as being able to say that .40S&W is "strikingly similar" to the 10mm--unless the 10mm is intentionally loaded down.

So, why did the FBI decide to decrease the power level of 10mm in the first place? Was it not because a lot of their agents couldn't use a regular 10mm level loading as effectively as they needed to? And as a result, essentially, opted for .40 instead of 10mm? Does this not speak VOLUMES?

Heck, why was .40 invented in the first place?

Why is .40 is more popular than 10mm by far amongst the FBI, and pretty much any other law enforcement/government agency?

The proof is in the pudding.

 

[S.Crockett]

So, why did the FBI decide to decrease the power level of 10mm in the first place? Was it not because a lot of their agents couldn't use a regular 10mm level loading as effectively as they needed to? And as a result, essentially, opted for .40 instead of 10mm? Does this not speak VOLUMES?

Heck, why was .40 invented in the first place?

Because the limp-wristed/non-shooter-type Bureau recruits couldn’t handle the original high-performance loads.

To understand that, you‘d have to understand who the vast majority of FBI recruits are: accountants, lawyers, ‘hair & fiber’ grabbers (bachelor of science grads), forensic crime-scene specialists, Mulder & Scully wannabes, etc.

Why is .40 is more popular than 10mm by far amongst the FBI, and pretty much any other law enforcement/government agency?
The proof is in the pudding.

The FBI dumped the .40 Short-n-Weak for the even weaker, easier-to-qual-with 9-minimeter. “Proof is in the puddin’” right there, Roscoe.

 

[LookAtYou]

In the best 380 defense thread, I provided several links to why at least 12'' penetration:
https://www.thehighroad.org/index.php?threads/best-380-defense-load.922957/

You have ignored that there is nobody (no "expert", LE organization, government agency) that currently recommends less than 12'' penetration.
You again are citing 10'' as if not having an unobstructed shot to the vitals has not already been thoroughly explained.

In this thread, I provided the 357 vs 38 special example using Lucky Gunner testing, they both penetrate & expand the same in gel.
If you think penetration & expansion in gel is all that matters then you think the 38 to have equal ASAP incapacitation potential to 357 Mag; I don't.

In Lucky Gunner testing the 10mm Hornady 155 XTP expands to about .65 - if one thinks gel is the whole picture of bullet potential then they would expect .65 holes in tissue.
Tissue damage from a 10mm 155 XTP that I shot a deer with, approximately a 1 1/4'' hole:
View attachment 1175975

The bullet continued to make a hole bigger than a quarter (.95) in the heart:
View attachment 1175976

So NO I do not think all handgun bullets only produce crush damage the size of the expanded bullet or those would be ~.65 holes.

Back to the 38 special versus 357 Mag example, 357 Mag had a better reputation on the street for ASAP incapacitation than 38 Special; apply that to 40 vs 10mm.

Is it possible that bone could've played a part in the larger than bullet sized hole? Hydrostatic shock (or whatever the correct term is) in handgun rounds, even in .357mag, is and has been a highly argued topic. It's an interesting one imo, I might have an idea for my next thread...

 

[JohnKSa]

So, why did the FBI decide to decrease the power level of 10mm in the first place?

Because they were able to meet the required performance standard (penetration/expansion) they wanted with the reduced loading.

Was it not because a lot of their agents couldn't use a regular 10mm level loading as effectively as they needed to?

No. The round was never issued until after the reduced loading was developed.

And as a result, essentially, opted for .40 instead of 10mm?

There was no opting when the 10mm was first issued by the FBI. It wasn't until later that the .40 was adopted.

Heck, why was .40 invented in the first place?

Because S&W realized that they could take the FBI loading and put it into a cartridge that would fit into a 9mm sized pistol/magazine.

Why is .40 is more popular than 10mm by far amongst the FBI, and pretty much any other law enforcement/government agency?

Because it meets the FBI performance spec and fits into a 9mm sized pistol.

Because the limp-wristed/non-shooter-type Bureau recruits couldn’t handle the original high-performance loads.

Wrong. The FBI never issued those loads. They developed their reduced loading before they ever issued any 10mm pistols.

The FBI dumped the .40 Short-n-Weak for the even weaker, easier-to-qual-with 9-minimeter.

Once there were 9mm loadings that met their performance standards (penetration/expansion), they switched to the 9mm.

Would you be able to reasonably and consistently CC a G20?

I have CCed mine. I have 3 main modes of concealed carry. My G20 will work for one of them, not for the other two.

 

[Masonlaw1]

Because they were able to meet the required performance standard (penetration/expansion) they wanted with the reduced loading.No. The round was never issued until after the reduced loading was developed.There was no opting when the 10mm was first issued by the FBI. It wasn't until later that the .40 was adopted.Because S&W realized that they could take the FBI loading and put it into a cartridge that would fit into a 9mm sized pistol/magazine.Because it meets the FBI performance spec and fits into a 9mm sized pistol.Wrong. The FBI never issued those loads. They developed their reduced loading before they ever issued any 10mm pistols.Once there were 9mm loadings that met their performance standards (penetration/expansion), they switched to the 9mm.I have CCed mine. I have 3 main modes of concealed carry. My G20 will work for one of them, not for the other two.

Great post! Many won’t let your facts get in the way of their stories, but good to see you got it out there!

 

[LookAtYou]

Because they were able to meet the required performance standard (penetration/expansion) they wanted with the reduced loading.No. The round was never issued until after the reduced loading was developed.There was no opting when the 10mm was first issued by the FBI. It wasn't until later that the .40 was adopted.Because S&W realized that they could take the FBI loading and put it into a cartridge that would fit into a 9mm sized pistol/magazine.Because it meets the FBI performance spec and fits into a 9mm sized pistol.Wrong. The FBI never issued those loads. They developed their reduced loading before they ever issued any 10mm pistols.Once there were 9mm loadings that met their performance standards (penetration/expansion), they switched to the 9mm.I have CCed mine. I have 3 main modes of concealed carry. My G20 will work for one of them, not for the other two.

So, and in agreement with my original post, it seems the FBI (and many others) agree that straight brute ballistics isn't the end-all-be-all for deciding what the best ccw choice against other people (not animals), otherwise hot 10mm would be preferred choice. Rather, it's ability for quickest follow up shots (9mm) and good shot placement, with still sufficient ballistics.

Why decrease 10mm power level in the first place? Because they knew what the drawbacks of regular (ignoring hot) 10mm was for most people. Because it makes it easier to shoot (thereby a more effective weapon), point blank period. No pun intended.

.40 S&W>10mm for ccw against other people. (Smaller weapon platform, quicker follow up shots, better shot placement, less chance of over penetration, I mean c'mon...)

Defense against a black bear? Another story.

Edit: Or Brown Bears (this one could be risky with only 10mm), deer, etc., you get the point.

 

[JohnKSa]

So, and in agreement with my original post, it seems the FBI (and many others) agree that straight brute ballistics isn't the end-all-be-all for deciding what the best ccw choice against other people (not animals), otherwise hot 10mm would be preferred choice. Rather, it's ability for quickest follow up shots (9mm) and good shot placement, with still sufficient ballistics.

They have a pass/fail criteria based on a complicated testing protocol that assesses penetration and expansion. If a round passes that testing protocol, it is eligible for selection. Then selection would proceed based on other factors, including, I would assume, things like cost, suitable firearm availability, "shootability". If you're asking, are they looking for the most powerful round possible, then the answer is obviously no, or they would have picked the .44AutoMag or something similar back in the 1980s when all this really kicked off.

Because it makes it easier to shoot (thereby a more effective weapon)...

Of course, they are not idiots and so they don't pick cartridges based purely on terminal ballistics. I've made the point repeatedly over the years that terminal ballistics is only one of several important criteria when it comes to weapon/cartridge selection.

.40 S&W going the way of the dinosaurs?

What everyone is forgetting is that the .40 is like the .45; a red, white, and blue, U.S.A. through and through, American as apple pie and mom caliber that will be used by red blooded Americans of strong mind and body until phasers are available. The 9mm is a decadent, wicked, teutonic wench of...

www.thehighroad.org

But the point is that if you can get the same performance out of 9mm that used to be only available from .40, then what's your motivation for continuing to give up capacity and dealing with extra recoil? If you were happy with the performance you were getting before, now you can have that same performance but with more capacity and better shootability.

After all, if it was just about increasing terminal performance to the maximum available and nothing else mattered, then we'd all be carrying .460 Magnums around.

We get so focused on terminal performance sometimes that we forget that there are other parameters that are important when selecting a sidearm.

.40 S&W>10mm for ccw against other people.

You could make this argument for .40S&W if you base your terminal ballistic pass/fail criteria on the FBI testing protocol. You could also now make the same argument for 9mm over both 10mm and .40S&W, given that there are now 9mm loadings that satisfy the FBI protocol.

Defense against a black bear? Another story.

Female black bears tend to have similar body weight ranges as an adult human male, and the average body weight for a male black bear is, according to some resources, 275lbs, about what a very large human male would weigh although there are certainly some outliers that grow much larger than that. Based on that, it would seem that something from the service pistol caliber performance class would not be a terrible choice for self-defense against black bears.

 

[DesertFox]

There are good deals to be had when the masses decide to bail on a caliber such as 40S&W. OG 10mm nut here but won't pass on a good buy in 40S&W. G22C, G27 and P2000sk all in 40S&W picked up at very fair prices. All 100% reliable for EDC.

 

[LookAtYou]

There are good deals to be had when the masses decide to bail on a caliber such as 40S&W. OG 10mm nut here but won't pass on a good buy in 40S&W. G22C, G27 and P2000sk all in 40S&W picked up at very fair prices. All 100% reliable for EDC.

I'd say 10mm would go before .40S&W. I don't see .40 going anywhere any time soon. Not even close. Its spot is solidified.

 

[someguy2800]

I'd say 10mm would go before .40S&W. I don't see .40 going anywhere any time soon. Not even close. Its spot is solidified.

Neither is ever going to completely die but its hard not to notice that nobody is making any new models of any kind in 40. Seams to just be going on momentum at this point. And I say that as a 40 s&w fanboy.