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

LookAtYou

Member
Joined
Jan 25, 2020
Messages
266
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. Generally, increased risk of over penetration compared to .40. Also can make a slightly heavier ccw setup than a .40 setup, due to slightly heavier guns and ammo.This definitely packs a wallop, more than .40 generally can, but at a COST.

Example: Glock 29 (Standard mag capacity of 10 rounds/3.78" Barrel).

*Results from Glock 29/3.78" Barrel)*
Ammo: 180gr Buffalo Bore JHP @ 1269 FPS/644 Ft-Lbs Energy (5-Shot Avg). 18.36" Penetration/0.7" Expansion (5-shot avg).

Screenshot_20230912-132551.png

.40: Very similar to 10mm, but generally less power (ft-lbs energy), expansion (similar in a lot of cases), penetration (this is where 10mm has the most notable advantage over .40 in my opinion, possibly even to a fault, i.e.10mm edging a little too close for comfort into over penetration risk territory), and LESS RECOIL and LESS MUZZLE FLASH, in general. Likely to come in a lighter ccw package than 10mm due to gun and bullet weight.

Generally, it's easier to shoot, offers quicker follow up shots, less muzzle flash, basically makes it easier to achieve good shot placement, less risk of over penetration, and a very proven round. Let's not forget how capable of a round .40 is, with loads getting more expansion and penetration than the BEST 9mm loads. A 0.67" hole on the deeper side of FBI penetration standards (15"+)? Ask yourself, realistically, how much more do you really need?

Example (s): Glock 23 (Standard mag capacity of 13 rounds/4.02" Barrel).

Smith and Wesson M&P40c (Standard mag capacity of 10 rounds/3.5" Barrel).

Ammo:
*Results from M&P40c/3.5" Barrel*
180gr Winchester Defender Bonded JHP @ 979 FPS/383 Ft-Lbs Energy (5-shot avg). 17.02" Penetration/0.67" Expansion (5-shot avg).

Screenshot_20230912-132609.png


In conclusion, the main disadvantages of 10mm compared to .40, and why, in my opinion, 10mm is not better for the VAST majority of people for ccw/self-defense against humans, is....
- Higher chance of over penetration compared to .40. I guess this is why 10mm is highly routed for use against animals, but this goes away from the focus of this thread, which is humans.

- In general, more recoil, muzzle flash, and noise than .40. In an average ccw sized package, 10mm ammo self defense ammo seems downright obnoxious. And the more you lessen the power of a normal 10mm load, guess what cartridge it's becoming more and more like... If one can "handle" 10mm, especially in a ccw sized package, how much better a .40?

- More chance to completely MISS, compared to .40!

(In my opinion) When it comes to defending against humans, 10mm makes for an unnecessarily obnoxious ccw/self-defense platform when compared to the .40. Also, it seems to border the power/penetration limits for safe usage in ccw/self-defense situations, against other people, to unnecessary limits.
 
Last edited:
I own handguns in both 40S&W and 10mm. I always liked 40S&W better for CCW. My 10mm Auto was a revolver. It was used almost exclusively with 40S&W for years in competition. Though later when I switch revolvers for competition I did deer hunt a few season with it loaded with 10mm. It worked well on deer. For CCW I don't feel any need to carry 10mm, 40S&W does that role as well or better for me. But for the past few years my CCW is more often 38 Special than anything else. YMMV
 
Last edited:
I 100% agree with you. If I didn't spend time camping and hiking in areas where bear are a potential issue I'd not own a 10mm pistol. For me 10mm fills a small, but important niche.

I've owned a 10mm pistol for 20+ years. It is normally only carried when I'm hiking/camping in bear country. If I'm only concerned with 2 legged predators my 9mm or 45 ACP pistols are more than sufficient. Nothing wrong with 40 S&W, but I feel I have my bases covered without one, and I've owned a few in the past.

10mm is versatile enough that with less powerful loads to be perfectly fine for human threats. I've camped in Yellowstone and Montana twice and plan to go back next summer for a 3rd trip. I won't carry 2 guns. My 10mm pistol will be loaded with 200 gr hardcast loads at 1200-1300 fps when camped and hiking. But I'll also take several pre-loaded magazines with loads much closer to 40 S&W power levels. In fact all 3 of the 10mm pistols I've owned shot 40 S&W ammo just fine and they could be used in an emergency.
 
The ballistics of the 10mm overlap the ballistics of the 357 magnum. If you would carry a 357 magnum for self-defense, a 10 mm works just fine. I find the recoil of a 10mm 1911 to be about the same as a 45 ACP +P or a four-inch 357 magnum revolver.

When I go to the handgun range at the gun club, I shoot my 460 S&W magnum, my 44 magnums, and then my 41 magnum. When I get to the 45 ACP and 10mm carry guns, they are a piece of cake.
 
I may have this all wrong, but I was under the impression that the OP's assessment mirrored the FBI experience with the 10mm, leading to the development of the .40 S&W. I don't go where bears go, so 38/357 meets my needs.
Just a couple points the FBI never issued full power 10mm, they basically knew going in there was too much blast and recoil for the average agent to shoot well. The load they tested and eventually adopted was a handload with a 180gr (Sierra JHC IIRC) loaded to 980 FPS. Back in the early 90s I acquired a few boxes of the Federal FBI loading and a big box of brass imma still using.
 
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. Generally, increased risk of over penetration compared to .40. Also can make a slightly heavier ccw setup than a .40 setup, due to slightly heavier gun and ammo.This definitely packs a wallop, more than .40 generally can, but at a COST.

Example: Glock 29 (Standard mag capacity of 10 rounds/3.78" Barrel).

*Results from Glock 29/3.78" Barrel)
Ammo: 180gr Buffalo Bore JHP @ 1269 FPS (5-Shot Avg). 18.36" Penetration/0.7" Expansion (5-shot avg).

View attachment 1171330

.40: Very similar to 10mm, but generally less power (ft lbs energy), expansion (similar in a lot of cases), penetration (this is where 10mm has the most notable advantage over .40 in my opinion, possibly even to a fault, i.e.10mm edging a little too close for comfort into over penetration risk territory), and LESS RECOIL and LESS MUZZLE FLASH, in general. Likely to come in a lighter ccw package than 10mm due to gun and bullet weight.

Generally, it's easier to shoot, offers quicker follow up shots, less muzzle flash, basically makes it easier to achieve good shot placement, less risk of over penetration, and a very proven round. Let's not forget how capable of a round .40 is, with loads getting more expansion and penetration than the BEST 9mm loads. A 0.67" hole on the deeper side of FBI penetration standards (15"+)? Ask yourself, realistically, how much more do you really need?

Example (s): Glock 23 (Standard mag capacity of 13 rounds).

Smith and Wesson M&P40c (Standard mag capacity of 10 rounds/3.5" Barrel).

Ammo:
*Results from M&P40c/3.5" Barrel*
180gr Winchester Defender Bonded JHP @ 979 FPS (5-shot avg). 17.02" Penetration/0.67" Expansion (5-shot avg).

View attachment 1171331


In conclusion, the main disadvantages of 10mm compared to .40, and why, in my opinion, 10mm is not better for the VAST majority of people for ccw/self-defense against humans, is....
- Higher chance of over penetration compared to .40. I guess this is why 10mm is highly routed for use against animals, but this goes away from the focus of this thread, which is humans.

- In general, more recoil, muzzle flash, and noise than .40. In an average ccw sized package, 10mm ammo self defense ammo seems downright obnoxious. And the more you lessen the power of a normal 10mm load, guess what cartridge it's becoming more and more like... If one can "handle" 10mm, especially in a ccw sized package, how much better a .40?

- More chance to completely MISS, compared to .40!

(In my opinion) When it comes to defending against humans, 10mm makes for an unnecessarily obnoxious ccw/self-defense platform when compared to the .40. Also, it seems to border the power/penetration limits for safe usage in ccw/self-defense situations, against other people, to unnecessary limits.
I liked your post, for the great topic, but I still often carry a 10 mm for self defense…and sometimes a .40. To each their own :)
 
I have always figured 10mm would be a superior round for shooting through barriers like windshields and car doors. Never having riddled an abandoned car with bullet holes to compare penetration of different rounds this is mostly just conjecture. I have also reasoned that a mix of FMJ and JHP projectiles would be the preferred loading in an urban environment.

I have never been able to talk myself into the need for a 10mm pistol. My standard carry guns are .32acp, .380, 9mm and 45acp. I have just recently added a .40 S&W (Glock 27 clone). I generally lean towards the smallest lightest weapon in the largest caliber possible for my clothing on any particular day. When I go to the big city I usually carry a .45acp (Kahr CM45, XDs sub compact or XD mod 2 double stack sub compact). A 10mm (like a XDm subcompact) has often crossed my wish list but I have never been able to justify having one other than better penetration of barriers.

I don't believe any caliber listed here would penetrate common body armor with FMJ. It would seem like a tungsten or hardened steel core would be needed against low level body armon.
 
I like 40 and really like my Glock 22.5
That said, I do not think penetration & expansion in gel completely reflective of ASAP incapacitation potential.
An example that most will should might understand:
https://www.luckygunner.com/labs/revolver-ballistics-test/
4'' barrel Remington 125 SJHP 357 Mag - 13.6'' / .54 - 1,473 fps - 602# KE
4'' barrel Remington 158 LSWCHP +P - 13.4'' / .56 - 921 fps - 298# KE
Penetration & expansion in gel is near identical for those two bullets.
I (and probably most other people) think 357 Mag has better ASAP potential than the 38 special - it has 2x the KE.

Higher chance of over penetration compared to .40. I guess this is why 10mm is highly routed for use against animals, but this goes away from the focus of this thread, which is humans.

Overpenetration? Pick the right bullet.
https://www.luckygunner.com/labs/10mm-auto-self-defense-ammo-ballistic-gel-tests/
Hornady 155 XTP - 14'' / .68 - 1,344 fps - 622# KE
Hornady 180 XTP - 16.9'' / .64
Winchester Silvertip - 16.2'' / .68
None of those are over penetrative. 🙄

Now to tie back to my 357 vs 38 example.
https://www.luckygunner.com/labs/self-defense-ammo-ballistic-tests/
Federal 165 gr. Tactical Bonded - 14'' / .73 - 978 fps - 350# KE

If we think the 357 Mag has better ASAP potential than the 38 Special - then we must apply the same to this 10mm vs 40 example.
I can't quantify it, but I think the 10mm has better ASAP incapacitation potential than the 40 - same shot placement is assumed.
 
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.
 
Subsonic .40/180 gr. Winchester government over-run, and the Glock G23.4:



Should work fine.

I'd agree, great round. And people call .40 "dead/dying" or "Short and Weak". What's weak about a 0.65"+ hole with deep penetration? The energy level compared to one of the most powerful common semi-auto calibers (10mm)? I get it may be a joke or trolling or whatever, but if people ACTUALLY believe that, there's a problem 🤣.
 
Last edited:
In my opinion, nearly all handgun rounds are badly underpowered for defense. It's funny how people who wouldn't dream of hunting a 200 pound animal with something like a .40 S&W will turn right around and claim that anything more powerful than a .40 S&W is too much against an enraged 200 pound attacker.

Overpenetration is a concern with just about any cartridge. That's why we often choose bullets designed to minimize it.

The only real downside of the 10mm - and other relatively powerful handgun cartridges - is recoil. Even us manly men who don't mind it are still going to have slower splits, especially in something like a Glock 29. Whether that is a problem is up to each individual.

That's not to knock the .40, which is still a fine cartridge, and is a great choice for a gun you can conceal in your purse. :neener:
 
I've done a lot of comparisons between the two in quickload and also chrono testing my own handloads. If they are both loaded to the same pressure there is about 80-120 fps difference between the two. Factory 40 s&w ammo is loaded pretty light. If you run the numbers in quickload to match most factory 40 s&w ammo you get something like 25k psi, when the saami pressure limit is 35k psi. Some people seam to think 10mm is a magic super cartridge. I've seen lots of people say 10mm is 300 fps faster than 40 s&w and that is just not true unless the 10mm is loaded to atomic levels and the 40 is weak FBI velocity spec loads. When I simulate some of these loads people talk about in 10mm with quickload, I can't match them without going up to 40k-45k psi in some cases. There is notable difference between the 2, but its not as big a difference as people will lead you to believe if you actually treat them both similarly.

I've had a couple glock 10mm's and I have shot 10mm 1911's and a tanfoglio. The double stacks have too big of a grip circumference and I feel like I'm shooting a brick, so they didn't really appeal to me. I do like 10mm 1911's but not enough to justify keeping a stock of another type of expensive brass and magazines. I don't really feel a big enough difference in recoil between a warmly loaded 40 and 10 to care about. I like the gun options in 40 better and its logistically easier to feed since the brass is a lot cheaper as well as factory ammo. I have an SR40, a kahr P40 a glock 22, and a sub2000 in 40. Every now and then I think about trying the S&W M&P 10mm but there just isn't enough difference there for me to justify getting back into 10mm. As for heavy bullet loads, I've shot thousands of 200 grain hard cast 40 s&w loads but I've never tried a 220. My 200 grains leave my SR40 at 1070 fps and like 1040 from my P40.
 
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).
 
Back
Top