Sit Down .40 S&W, .45 ACP — The 9mm has Been Crowned King?

Glock 22s and a Glock 23

For years, I have suffered the insults, ridicule, jokes and consternation of my fellow shooters. The 1911 crowd was never a surprise. After all, there is the classic 9mm vs. .45 ACP debate. With the advent, and near-immediate acceptance, of the .40 S&W, the 9mm’s position did not approve—nor did mine.

After years of suffering (not exactly in silence…), I finally broke down when I bought a Glock 22 in .40 S&W. The increased recoil alluded to the increased knockdown power the bullet would deliver; I was instantly intrigued. Of course, if the .40 S&W was better, what about the .45 ACP? Not that I am “gun-greedy” or anything, but strictly for, ahem, “research purposes,” a new 1911 was quickly and quietly (lest the wife or caliber foes discover my new acquisition) acquired.

multiple firearm cartridges
L to R: .45 ACP, .357 Mag., .40 S&W, .357 SIG and 9mm. It is not always the biggest cartridge that’s the best for the job or the best shooter.

A Glock 23 and SIG P250SC soon followed—both chambered for .40 S&W—the Glock 22 and 1911. I began to wonder if I had been relegated a closet 9mm admirer. Should I truly retire the SIG 228 I had trusted for close to two decades believing it to be inferior? Not a chance. In fact, quite the opposite was true. Shortly after ordering a new Glock and being sent a second Glock 22 by accident—the model was wrong, but the customization was too cool to allow me to send it back—I decided I wanted to shoot both a less powerful and more powerful cartridge out of the Glocks.

Instead of believing the 9mm to be inferior, I simply decided new barrels were required for the Glocks. I jumped online and ordered four new barrels and a few 9mm magazines. Excited, I waited by the door for the delivery that would allow me to shoot 9mm, or .357 SIG, in addition to the .40 S&W, out of the Glock 22 or 23. A significant number of rounds from all three calibers soon followed.

With options, I can now shoot the caliber de jour, but most often find myself going back to the 9mm, and here are my top eight arguments why.

1. Don’t believe old data or old tired arguments.

Perhaps, once upon a time, the 9mm was less than optimal for self-defense. That being said, I do not know of anyone that would hold still just because a 9mm was pointed at them. Since then, technological advances in bullet design and propellants have transformed the 9mm into a much more powerful pill than in the past. These advancements have not been lost on some of the nation’s top law enforcement departments or the military. The reasons leading this new reacceptance of the 9mm include lower training costs, reduced recoil to the shooter, faster target reacquisition for follow-up shots and increased knockdown and soft tissue damage.

.40 S&W, 9mm and .370 SIG barrels
Notice the difference between the thickness of each barrel. A frame built for the .40 S&W will accept smaller calibers with thick barrels, but a purpose built 9mm will not work for larger calibers.

2. I shoot the .45 ACP for competition so why not self defense?

It is true; you can be accurate with the .40 S&W or .45 ACP in competition. Many of these guns are also modified specifically for competition and the cartridges are toned down to decrease recoil. (However, even if you shot the competition just as well with a stock gun and self-defense ammunition… Yeah, that’s never really going to happen, so let’s not even entertain the fantasy.) Whatever level of accuracy and speed you can muster with the .45 ACP or .40 S&W, you’ll match, or more likely exceed, with the 9mm.

Do the bigger calibers have more knockdown power and a better chance of stopping the threat with a single shot? According to DOJ statistics, they do. However, that is a generalization. Shot placement is the most deadly consideration in a gunfight.

The lighter 9mm may be at a slight disadvantage for the first shot, but it offers a huge accuracy advantage for follow-up shots. Does anyone reading this carry a single-shot pistol for self-defense? If not, you must consider the possibility of a follow-up to be a real concern and acknowledge an advantage to the 9mm.

3. I have so many choices in 1911s. How does the 9mm compare?

More handguns are made for the 9mm than the larger calibers. This equates to more choices and a better possibility of finding the gun that fits your hand, style of shooting and purpose. Handguns are being designed with grip options that allow you to customize the platform to the shooter. Concealed carry is also more popular than ever. The smaller the caliber, the more concealable many models become. Again, this gives the 9mm an advantage in size, but let’s not forget, it also has an advantage in weight.

4. The 1911 .45 ACP has been around for over a century, what about the 9mm models?

While the 1911 design is indeed over a century old, not every 1911 has seen regular service for the last 100 years. Typically, the 9mm will see less wear and tear than its bigger caliber brethren. Because few of us have the budget to adequately test longevity, we can look to data from various government agencies that log 9mm handguns sustaining as much as 100,000 rounds during their service life. This cannot be said from the larger calibers. The longer service life also equates to less repairs and catastrophic failures from high round counts.

Tan Glock 22 with .40S&W, 9mm and .357 SIG barrels
By picking up a couple of extra barrels, you save some serious cash compared to the cost of a couple of extra guns. Switch out a barrel and perhaps a magazine and you have an entirely new gun.

5. Magazine Capacity

Magazine capacity is rather a double-edged sword and an argument that is seldom fully developed. The argument in favor of the 9mm is simply a larger capacity. Compared to the 1911, several models of 9mm will carry twice as many rounds. However, more rounds means more weight. Thus, twice as many 147-grain 9mm will weigh more than half as many 230-grain .45 ACP. More weight in the magazine is often forgotten when the shooter reads the manufacturer’s specifications and notes the weight of the gun unloaded.

A couple of arguments regarding magazine capacity are worthy of consideration. First, on average, less than four rounds (3.8 as I recall reading in a DOJ report a year or two ago) are fired in a self-defense or law enforcement encounter. This begs the question; would you rather have more rounds than you need or risk being short of lead when you need it most? There is also the possibility of carrying spare magazines, but that tips the scales back to the 9mm concerning the weight argument. Likewise, there is the matter of time to swap mags during the heat of an engagement to consider.

6. 9mms can be finicky and not shoot certain types of ammunition.

While it is true that every firearm should be tested thoroughly to ensure it will reliably digest a steady diet of your favorite ammunition, the 9mm has the edge over the 1911, but not other large caliber handguns. The 1911 was designed to handle ball ammunition and models true to the original design show a weakness in the modern era while attempting to shoot modern self-defense offerings. However, manufacturers have realized this and now offer a wide selection of 1911 models with improved feed ramps, wider ejection ports and other features that allow them to better handle these modern self-defense loads. As for non-1911 handguns chambered for the .45 ACP or .40 S&W, I have never found any feeding disadvantage when compared to their 9mm counterparts, but also no feeding advantage.

7. Selecting the Right Ammunition for Practice and Self-defense

The .45 ACP has a bit of an advantage here. In my SIG 1911 C3, I carry SIG’s Elite Performance Ammunition with its V-Crown hollow point technology. However, I cannot argue with the military’s performance record using .45 ACP ball ammunition for practice or against a determined adversary. While the 9mm does not offer the same practice and self-defense potential from a single round, it does offer a much wider selection for either practice or self-defense ammo at a much cheaper price.

For example, the 9mm is commonly loaded with 115-grain +P to achieve a high velocity. Standard 115-grain offerings are great for practice and cause less stress to both the shooter and handgun. Alternately, it can be loaded with 147-grain loads, which offer a lower speed, but a pill with more kinetic energy by comparison.

Glock 22s and a Glock 23
The only way to determine the best gun and caliber for you is to do some range testing of your own. Find the caliber that will put the most rounds in the vitals and set your ego aside.

8. There is simply no comparison between costs.

Likely the number one justified criticism against shooters is that they do not get enough range time. I am a huge fan of laser trainers, SIRT pistols and dry-fire practice sessions to build and maintain skills. However, practice with a trainer is still lacking compared to actually sending lead down range. While few of us will ever have the time and finances necessary to shoot as many rounds as we would like, the 9mm is smaller and therefore uses less raw materials. This makes it cheaper to produce and more affordable. Regardless the size of your budget, this will equate to more rounds for the same amount of cash—the rest is up to you.

Parting Thoughts

Make no mistake in reading this. I favor the 9mm cartridge… for me. However, as I alluded to in the beginning, I have been buying .40 S&W guns for the last several years. The reason? It is simple. Most .40 S&W models can easily be converted to shoot the 9mm or .357 SIG if I so choose. However, the frame of a purpose-built 9mm is too small should I want to convert it to shoot a larger caliber.

custom SIG Sauer 228 with Cerakote and Crimson Trace Laser Grips
After a couple of decades and thousands of rounds, the author’s SIG 228 9mm has seen a few upgrades including a Crimson Traces laser grips and Cerakoting by J&L Gunsmithing.

My recommendation? Shoot whatever pleases you! It is your butt on the line not mine, so it is your decision… However, I would encourage you to enjoy some time at the range while doing your homework. Ensure whatever you choose to carry is truly the best choice based on your own testing, experience and capability, and not simply based on the rambling of an old gun writer such as myself or any of the esteemed nuts cases I hang out with. Then, compare your hit percentage and round placement when selecting a caliber for self-defense. Happy shooting!!!

What caliber do you prefer? Make your best case and share it in the comment section.


The Mission of Cheaper Than Dirt!'s blog, The Shooter's Log, is to provide information—not opinions—to our customers and the shooting community. We want you, our readers, to be able to make informed decisions. The information provided here does not represent the views of Cheaper Than Dirt!

Comments (209)

  1. I like the bigger hole is better theory. So my preferred CC is a 3 1/2 in. double action 45 ACP pistol. Of course the best gun to carry is the one you can shoot well.

    There is rarely a need to carry a high-capacity gun with a 30 round magazine for backup unless you make enemies very easily or live in a very bad neighborhood. However, I believe in freedom so a person should be able to carry whatever they want.

  2. I also picked up a full size Citadel 1911 with ambitious safety in 9mm just so I can have one for my left hand, and so I can shoot 9mm.
    I got 45 Long Colt, 45acp, 9mm, 380, 22WMR and 22lr covered for hand guns.

    1. The M1911A! is a Great Universal Translator, even to those that Can’t Speak English. No Surprises in it’s Meaning…

  3. Both 9mm Parabellum and .45 ACP scored at or near the top of the charts for effectiveness in many tests, so both are valid choices, and most of the arguing is really just gun dudes having fun talking to one another.

    But to break it down just a bit further, 9mm is, on average, a bit better penetrator, and .45 ACP will, on average, cause somewhat bigger wounds on less protected targets. 9mm lets you carry more rounds at the same weight, which is important for militaries seeking a “force multiplier” and is never less than useful, but is not always the most important concern for a civilian using the handgun in a self-defense capacity. Many of the best firearms are now available in both 9mm and .45 ACP variants, so platform is not always determinant either.

    .357 SIG is technologically superior to 9mm Parabellum (as we would expect, being much newer) and will likely supplant it some day. Right now, it is expensive, but is by far the most ballistically consistent handgun round available. .40 S&W, on the other hand, suffers from a much higher rate of case failure than the other options discussed here, and should be avoided.

    “Shoot whatever pleases you” is not really a recommendation, but it is what people will do anyway. Individuals should practice as described in the article, explore their accuracy, recoil tolerance, etc., and draw informed conclusions as to which caliber is working best for them.

    I like .44 Special myself ( ͡° ͜ʖ ͡° )

    1. @J You hit the nail on the head! After owning 7 different handgun calibers, I tried someones .357 SIG, and it was superior to all others in pretty much every way. If cost comes down, they will become insanely popular.

  4. I prefer a 1911 MEUSOC type pistol in 45 acp carried in a level 2 retention holster carrying 9 rounds condition one. The reason is that I have decided, based on my own experience, that if I am in a self-defense engagement its likely going to take place within hand to hand distances.

    Therefore I physically train to defend myself hand to hand as the primary self defense. Locking the 1911 into a level 2 retention holster assures that I do not have to think about or maneuver myself to prevent a gun grab. I can focus my full attention on the attacker and controlling their movement. If the attacker deploys a deadly weapon I train to draw my 1911 and defend myself at close quarters. My real life experience is this does not require any of what a 9mm pistol has to offer as discussed in this article.

  5. In actual shootings, all 3, 45 ACP, 40 S&W and 9mm have all done equally well at stopping bad guys. The small percentage difference is too insignificant to matter. There is no perfect bullets or calibers and anyone that thinks so is naive at best. I carry the “Baby Glock” model 26 and I don’t ponder a single thought of being outgunned. The great about lots of different guns and calibers is a person has lots to choose from. As I always, whatever spins your prop. Carry what makes you warm and fuzzy and leave it at that.
    Best wishes and stay safe everyone!

  6. .40 cal has more density for the size and was designed to punch hard. I was un biest for a long time until i had em all at the range .45 9mm .40. The .40 out performed everything with a bunch of different impact points. Lol honestly it tore things up. Not a big fan of .45. It s to wide for the speed it moves at- belongs in a revolver with more powder. 9mm and the shovey ftfive:) don t maximize the potential of this general size of firearm. If a person has a little common grasp on physics they d realize the .40 performance is more well rounded and can be loaded for various situations. Please dont ask me to post ” my sources” go shoot em all somehow and give thought to bullet shape, size and velocities. It really is common sense that it would perform better.

  7. Having both a XDm 9mm, with a 3.8″ barrel, holds 20 rounds and an full size, XD 5″ Service pistol that holds 12, I’ve shot both many times. The 40Cal does have more knock down power, but is harder to get back on target for double taps, etc., and can be quite “snappy.” The 9MM is sort of sneaky, IMO. It has less kinetic energy/FT LBS. than the 40Cal, but if you use a +p or +p+ load, the velocity is amazing in the 9MM! The extra velocity makes up for having a bit less energy and creates for hydrostatic wound capability. So in a defensive situation, for me, it’s a toss up. Pick a great load for the 9MM, Golden Sabers, and you have a really great gun. BTW, depending on the load, the 9MM 115gr. can have more energy at 10-20 yards than a 147gr. I do a lot of research on my defensive loads!! This, again, is due to the considerably higher velocities reached by a +p 115gr load. I carry the 3.8″ XDm 9MM daily. I live in AZ, so it’s legal here for concealed carry.

    1. Amen brother! I have the XD mod.2 9mm 3.8inch barrel 16+1 and I LOVE IT! Am currently testing different ammo to find what’s best for my self defense wants. God bless!

  8. Such a challenging question. I’m not a tester but user. Leo since 1984. Started two agencies with 357 Mag wheel guns. Converted to 9mm with the first as department changed. Being pc for the time, press was an issue, so we went from softnose 357 to Silvertip 9mm. Two ends of the spectrum. By the time they figured the fools erand with an expanding alumni mum bullet, I was back to 357 Mag in another agency. Then we had the 155 grain 40cal built just for us and they had to retool the berretta and give it a new designation the 96D. Changed agencies and learned to love the 357sig/p229 combo. Yep, they are sure to stop before exiting the skin of an aluminum aircraft. Back to second agency to usher in the H&K P2000 again modified for our 155 grain super duper hot 40. So twilight of career and they switched us to 180 grain 40, new design, with equal to or better balistics (plus the blue third can keep more folks qualified because they didn’t transition from the 9mm with ease, that recoil you spoke of, they made another special round 135 grain 40 -soft recoil- just for them.) And now we only have to buy one bullet weight and the guns last longer than they did with the hot 155/40. I agree with you, have guns that can perform with what works best for you, but in your goody bag have the parts so when , and if..wink…wink.., you can use the bullets to be found in the future less than optimal conditions. After all, till then hopefully all we will be doing is training for those times. Have a blessed day. May the Lord come before those times are upon us. Till then, get prepared.

    1. @ Ed McRight.

      Consider the .960 Rowland instead, A 9x23mm +P “Wildcat” Round with 38,500psi Bore Pressure. And 1,440ft/sec with 4.25-inch Barrel and 1,600ft/sec with 6-inch Barrel…

  9. I say shoot what you are comfortable with, There is not a whole lot of difference, But to say the 40 or 45 is inferior to a 9 is just wishful thinking you can see in all the ballistic gel test when hit with a 40 or 45 the whole thing jumps not so with the 9 penetration it does all right if using +p+P or what ever, Then they say the 40 is hard on a gun, I happen to like my 5 shot 4.25″ SP 101 I do not feel undergunned at all and do not need 17 rnds to get the job done, In a real world gun fight if you shoot 17 times YOU are probably going to be in real trouble anyway Its very important to make your shots count, YOU are responsible for each round coming out of that weapon, And the fact a 9 is king is laughable, Most shoot a 9 better because of the lack of recoil PLAIN AND SIMPLE, A 8 or 9 round pistol in 22 mag to the face is deadly also all hail the 22 mag????

  10. Thanks to contributors … Me? Sig P938 9mm w/ Houge rubber pistol grip and extended 7 round mag. Easy to conceal carry. Not to big or small, lightweight and $11 / 50 rounds for range is cheap! Carry w/ +P Remington BLACK BELT 124 Gr. Speed, accuracy, lightweight and concealable. Cocked and locked, 8 rounds. Not the weapon of choice for less ‘common sensical’ gun tote’rs’ or more fragile (older) men/women. She totes a S&W Bodyguard 38 cal. Revolver. Only two options to consider; laser or trigger. Double action with no hammer or safety. It’s plain and simple for someone not mechanical.

  11. So, what do you think of deer hunting, close range (inside 100 yards) with 40 ccal 180gr jhp?
    With our new carbines selling like hot cakes I had to try it…and love it!

  12. say what you want about the 9mm &.40 cal being the king of handguns,My every day carry of my S&W.500 or my DE.50 are my king of handguns.

    1. My every day carry of my S&W.500 or my DE.50 are my king of handguns.

      So Kennith, print much?

      Concealed carry assumes the “concealed” part.

  13. @ ss1.

    An easy comparison is, the next time you Look At An Old Tubular Metal Bicycle. The Mil-Spec. Barrel is made of the SAME METAL, AISI/SAE 4140 or AISI/SAE 4150 Steel…

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