9mm vs. 40 S&W: Ending the Concealed Carry Debate

The 9mm vs. 40 Smith & Wesson (40 S&W) debate has been raging since the introduction of the 40 S&W in early 1990. The debate centers around which of the two pistol cartridges is superior for concealed carry.

Let’s take an objective look at the 40 S&W and see how it stacks up against the 9mm – the most popular centerfire handgun round in the world.

I hope you have a full pack of silhouette targets and several boxes of FMJ ammo. You’re going to need them as we take our shot at the 40 S&W vs. 9mm personal defense ammo debate!

40 S&W vs. 9mm: The Differences Between 40 and 9mm

Let’s start with the top three points of contention when it comes to the 40 S&W vs. 9mm discussion: stopping power, magazine capacity, and recoil.

9mm vs. 40: Stopping Power

Stopping power (aka knockdown power) is one of those ambiguous terms shooters like to throw around to justify their position on one cartridge or another. There is no column on the ballistics charts for stopping power. In truth, it is a combination of several factors including striking energy, wound cavity diameter, penetration depth, and shot placement.

Although stopping power cannot be quantified, it is essentially the rate at which the bad guy reaches a state of incapacitation. Once the threat is unwilling or unable to continue, you’ve survived the fight.

A 40 S&W to the foot is a lot less lethal than a 9mm to center mass. However, with all other things being equal, the 40 S&W is going to hit harder and cause a larger permanent wound cavity as it is loaded with a wider and (usually) heavier bullet compared to a 9mm.

The 9mm diehards are going to expound on the fact that advancements in JHP technology have brought the 9mm round to the same level as the 40 S&W in terms of terminal expansion. I’m not sure if I’m willing to go that far.

It cannot be denied that a 40 S&W will cause a larger permanent wound cavity and exhibit better terminal performance than a 9mm, but the average shooter typically has better shot placement with the 9mm. The 40 S&W only edges out the 9mm by a hair.

The biggest issue many detractors of the 40 S&W bring up is the amount of recoil the cartridge has, which will directly affect shot placement.

On that note, let’s discuss recoil!

9mm vs. 40: Recoil

The 40 S&W is difficult for many shooters to handle due to its snappy recoil. 9mm loads have about 25% less recoil than the 40 S&W. For an experienced shooter, that added recoil will not be too difficult to handle. However, for a new shooter or one with smaller hands, it can be incredibly difficult to handle the recoil of a 40 S&W.

No matter how you slice it, a shooter utilizing a 9mm round will experience less recoil. That means they can reasonably expect faster follow-up shots and generally improved accuracy compared to using a 40 S&W.

9mm vs. 40: Magazine Capacity

Magazine capacity for the 9mm and 40 S&W is very good. One draw to the 40 S&W is that you typically get to fire a heavier bullet without having to forfeit more than a few rounds of magazine capacity.

Comparing the 9mm Glock 17 to the 40 S&W Glock 22, the difference in magazine capacity is only two rounds. That’s pretty good.

However, two rounds are two rounds. They could spell the difference between engaging another threat or having to reload.

Though the difference is small, the 9mm does allow for higher magazine capacity. In no uncertain terms, it lets you carry more ammo in the same amount of space (read: in a similarly sized firearm).

9mm Pistol Magazine Capacity Chart

9mm Pistol Magazine Capacity Chart

9mm vs. 40: Accuracy

New shooters occasionally ask me if the 9mm is more accurate than the 40 S&W, or vice versa. That’s not really the right question to ask. What they should be concerned about is which round they can fire more accurately.

Accuracy is primarily dependent on the shooter, not the cartridge or the firearm. If all other things were equal, shooters would experience almost identical accuracy between these two rounds.

However, many shooters discover they are more accurate with a 9mm. This is primarily due to the 40 S&W’s aforementioned heavier recoil.

9mm vs. 40: Home Defense and Concealed Carry

If I had to chose one of these rounds for home defense, my choice would be the 40 S&W. Engagements inside the home will be at very close distances. Under those conditions, you want the heaviest, most powerful round you can handle while still maintaining shot placement.

The 180 grain bullet provides excellent penetration and kinetic energy transfer into the bad guy without excessive risk of overpenetration that could jeopardize bystanders.

For concealed carry, the 9mm seems like the better option for several reasons.

First, a compact or sub-compact 9mm handgun has less recoil than a 40 S&W of the same size. Generally, this will result in better accuracy, and this is critical when you are out in public. The potential to hit an innocent bystander is higher in a public place. Every bullet you fire has a lawyer attached to it, so you want to make darn sure you hit what you aim at should you have to defend your life outside the home.

The second reason the 9mm is preferred for CCW is its higher magazine capacity. Generally, 9mm magazines have higher capacity than 40 S&W ones, so you can carry a few extra rounds for the same weight. More rounds are always better!

9mm vs. 40: Ammo Price and Availability

At the time of writing, 9mm and 40 S&W ammo are both plentiful with multiple bullet weight options available. The vast majority of 9mm Luger comes in 115, 124, and 147 grain varieties, while 40 S&W is mostly found loaded with 165 and 180 grain bullets.

Generally, premium JHP ammo is about $1 per round for both 9mm and 40 S&W. For FMJ practice ammo, you should expect to pay about $0.50 per round for 9mm and $0.60 per round for 40 S&W. This isn’t a huge difference, but 9mm FMJ ammo is typically cheaper. It’s utilized by the military. The 40 S&W is not.

Buying in bulk is always smart. Make sure to check out our stock of 9mm bulk ammo and bulk 40 S&W ammo.

9mm vs. 40 Ballistics

Our team here at Ammo.com has combed manufacturers’ data to help you compare 9mm vs. 40 S&W. For even more detailed 9mm performance data across additional manufacturers and loads, see our complete 9mm ballistics reference. These tables will allow you to see how your favorite bullet weight compares to others in terms of muzzle velocity, muzzle energy, and trajectory.

Continue reading here ➔ Ammoammo.com/comparison/9mm-vs-40

Source: https://freedombunker.com/2025/10/16/9mm-vs-40/