When .40 caliber first came out, it was apparently the coolest thing since sliced bread. It was powerful, offered a new type of effectiveness on a human threat that could not be matched well by other calibers, and Law Enforcement was jumping to it all over the place. Lately, people have started abandoning the caliber in favor of the 9mm for perceived improvements in bullet performance and technology. I will refrain from talking about caliber and getting into the debate on performance and such. My focus here will be whether the .40 caliber is a suitable round for combat or if the world got it right with the 9mm.
It is no secret that the .40 S&W is a heavier bullet when compared to the 9mm. The popular choice for most agencies that use the .40 is 180 grain. That is 30% heavier than the standard 124 grain loading for 9mm. Of course, 147 does exist, but not too many militaries are issuing it as a standard loading. The added weight of the individual bullets means more weight on your person. To me, two extra magazines with 15 rounds of 180 grain .40 S&W is only about 1/10 of a pound more than if I was carrying two magazines with 124 grain 9mm. Not really much of a difference to even matter in my opinion, but it is more for those who like to argue over numbers instead of experience.
It is no secret that most .40 caliber pistols out there are not going to have the same capacity as a 9mm. DUH! It is a bigger diameter and it is trying to fit in the same size magazine and platform as the 9mm. But if you look at it, there is really only a difference of 2 or 3 rounds in the magazine. Some oddities would be my Tristar C100 that has 11 round magazines for .40 S&W versus the 15 round magazines for 9mm. Even with the PX4 Storm, it holds 14 rounds of .40 S&W while the same magazine can hold 17 rounds of 9mm. But with pistols like the USP40, I am actually able to get 14 rounds in the magazine, which is only one round less than the 9mm. Even with the H&K P2000, there is only a one round difference in magazine capacity for the two calibers.
I guess the big question is whether capacity is rally the biggest issue ever in combat. Well, in my experience, there are two different types of situations that you can run into that will dictate how many rounds will be needed in a firefight, particularly in a pistol. First principle to remember is that range will be the ultimate factor. More range equals more time to deliver decisive shots. The closer you are, the less time you have on your side. But this also requires discipline and experience, which is not a common virtue, even in the military. Even I am guilty of often sending a few extra "FUCK YOU" rounds towards my target out of anger. But no, in my opinion and experience, two or three extra rounds are not going to rob you of your life. The .40 S&W in most pistols will have enough capacity to serve it's purpose. Many people will want those extra rounds in the magazine as a "feel good" measure, but that doesn't mean it is practical.
One of the biggest issues people have with the .40 S&W cartridge is that it is quite hard on pistols. This is true. For the most part, pistols have a hard time withstanding the pressures delivered by this cartridge. However, certain pistols are made AROUND the .40 S&W with the understanding of this cartridges pressures. Pistols like the H&K USP and the Sig P229 were made specifically to handle the .40 S&W. Personally, I think that pistols chambered in .40 S&W have a long enough service life to withstand plenty of training and combat. I think it is overblown that pistols chambered in .40 S&W require regular maintenance.If you really want to get technical about the pressures, the .40 S&W pressures are actually on par with the 9mm NATO. Just because the military is negligent at maintenance does not mean that we should change to a weaker cartridge just so we can shoot more paper before having to change a spring, especially when the .40 S&W has dang near the same pressures as the standard military 9mm NATO.
It is often reported by shooters that the .40 S&W is snapping and the recoil is just "TOO MUCH" for them to be able to get accurate hits of "FAST" follow up shots. I have been shooting alot of different calibers and I can tell you that you do get a bit more feedback in the .40 S&W cartridge, but it depends on the pistol you are shooting. I would argue that the PX4 Storm and the H&K USP tame the .40 S&W to the point that it is no more on recoil than 9mm NATO ammo. Even with those pistols that are not specifically designed to handle the .40 S&W, you will notice that the pistol goes back on target fact and that what you are getting is merely a feeling, and with a competent grip, it is just as fast getting back on target as a 9mm. Just my experience though.
It is no secret that the .40 S&W was born because of the failure of the 9mm. Realistically, it was made to basically be a weakened 10mm. But the point was that this bullet was supposed to deliver better terminal and barrier performance. This was one of the biggest reasons for people following the FBI in adopting the .40 S&W. But even today, the .40 S&W does a great job in barrier and terminal performance. On my YouTube channel, I tested a good amount of 9mm and .40 S&W hollow point loads, and one of them was the Winchester 180 grain JHP. It comes in a white box and is considered a very basic and "CHEAP" hollow point. I did some digging on the Winchester Law Enforcement website and I found that the .40 S&W is the only basic JHP design that actually meets and exceeds the FBI standards for terminal ballistics. It is not by much, but I found it interesting that it was above the rest even through barriers compared to all the other calibers. As a combat caliber, I think it is pretty awesome that the .40 S&W, without any fancy upgrades, is able to perform well, even through auto glass.
When it comes to cost, the .40 S&W is definitely going to cost a little more than 9mm. It is just the way it is but I think that the difference is not too much if bought in bulk. If the military were to invest in the .40 S&W, they would not be too happy when the cost per round is a penny or two higher. But in the grand scheme of things, I think that they would be okay with it since the government is and has always been okay with spending the money of other people. Lets be realistic, though. The military does not really have that great of a firearms training regimen. The methods used encourage bad habits that take years and tens of thousands of rounds to overcome. Other than that, the military rarely gives their troops enough range time to truly be proficient, so I think the cost portion is a bit of an overblown for the military. As someone in a militia or someone prepping for their combat wet dream, I think the benefits of the bullet outweigh the cost of becoming and maintaining proficiency. Realistically, most of the skill development and maintenance is in dry fire practice. But that is another subject.
I know I sounded like a used car salesman for the .40 S&W, but I was just trying to look at things realistically. If you don't think it is a good round for combat, that is on you. I personally think that it is a good option for experienced and skilled people who can handle it and are wanting to be able to deliver harder hits when they are down to using a pistol to defend their life. Ultimately, I feel that it all comes down to that. If you are using a pistol in combat, you are in a pretty bad spot, and I would hope you would want a pistol and a caliber that will give you a leg up in the fight. For all you know, it may make the difference between telling a story and having your story told by someone else. Personally, I would rather be the one to tell the story.
Do It Rite
Alaska-Based Youtube Vlogger, Retired Marine, Firearm and Gear Tester.