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Calibers of the Semiautomatic Handgun: The .40 Caliber

Eric J. Perry is a former firearms instructor for various police departments. He is an Army veteran.


The .40 Caliber: My Favorite Round

Every caliber has its purpose and its fan base. Just like cars, trucks, and sports teams there are people out there that love one and hate the other, or think one is terrible and the other is great. This is the reason there are so many options to choose. There are those that hate the .40 caliber and those that love it. Personally, it is my preferred round.

Just remember when it comes to all the varieties of rounds out there, no one is wrong and no one is right. Each individual must choose what is best for themselves.

In this article, we will discuss the history, ballistics, cost and availability, and my personal experience and considerations in choosing the .40 caliber cartridge. This article is specifically intended to discuss calibers because the ammunition is arguably more important than the firearm. The majority of malfunctions with a semiautomatic pistol are due to the ammunition.


The Importance of Ammunition

There are dozens of high-quality firearm manufacturers out there, but you only have to buy the pistol once. The ammunition must be continually replaced during use. For example, I purchased a .32 Magnum revolver for $60. A box of 25 rounds cost me $20 plus tax. That is just shy of $1 per round.

Additionally, I have been unable to find the rounds for sale anywhere other than a gun store and they rarely have more than a couple of boxes at a given time. Realistically, that is not a round that I can take to the range all day and shoot. The purchase was more for novelty than necessity.

When choosing a firearm and caliber, more practicality in availability and cost should be considered to allow you greater opportunity to practice without costing you a small fortune. By all means, if you find a good deal don’t pass it up. Just take everything into consideration.

Glock 22, .40 Caliber

Glock 22, .40 Caliber

Experience and Considerations

The .40 caliber round is my preferred round. It is a good balance between the .45 caliber and the 9mm. The .40 caliber has the capacity, weight and cost of the 9mm with the power of the .45 caliber. Understand though, that this is not an optimal round for everyone. The .40 caliber has a greater recoil (the kickback after firing) than the .45 because of the amount of power it has on the small frame of a 9mm.

We will get into that more in ballistics, but know that the .40 caliber kicks as much if not more than any other caliber. For example, my brother has smaller hands and cannot get a good solid grip on a .45 caliber pistol. He tried the .40 caliber but since he could not support the pistol like it requires he was less accurate with the .40 caliber. He purchased a 9mm with a lesser recoil and his follow-up shots greatly improved.

Accuracy is the most important factor in determining what caliber and firearm to use. It does not matter how big of a bullet you fire if it misses the target, you are ineffective. A well placed .22 caliber or 9mm beats a missed .45 caliber, every day.

My experience with the .40 caliber comes from my 6 years in law enforcement. I have carried a Glock .40 caliber on duty from day one. In the police academy, I won the Top Gun Award for the best qualification score among 41 cadets. I also used my .40 caliber Glock to successfully complete the FBI Certified Firearms Instructors Course. The .40 Caliber is capable of handling any situation and can deliver well-placed shots with adequate training.

I have had a .45 caliber and currently have 9mm, .380, .40, and .22 caliber pistols. Every one of them fire well, are accurate, fairly available, and reasonably priced. In the end, you, just as I, must choose a caliber handgun that we are the most comfortable and confident with carrying and operating. For me, that is the .40 caliber.

History of the .40 Caliber

The .40 caliber round is among the newest rounds on the market today. It is only 25 years old, having been developed by Smith and Wesson in 1990. This caliber has surged into popularity in a short time. You see the label ".40 S&W" (Smith & Wesson) on boxes of ammunition even though another company produced the ammunition. S&W developed the caliber after being approached by the FBI following the famous and fatal shootout in Miami in 1986. The Bureau searched for a handgun that would have sufficient stopping power and a higher magazine capacity than the .38 specials that agents were currently using.

The .40 caliber was modeled after the 10mm and put on the medium sized frame of the 9mm. That is the reason the recoil is as heavy as it is. In developing the 40 into a 9mm frame, S&W allow for the two cartridges to have interchangeable frames by simply changing out the barrel and magazines.

In critical situations, the 9mm round can be fired from a .40 caliber barrel but this will cause damage to the gun, particularly the barrel. Again, this is not recommended or suggested but in a life-or-death situation it can be done. Please do not test this out and I pray you are never in a situation that requires the need to do this.



In this section, We will talk about ballistics of the .40 caliber cartridge. My intent is to simplify this so that every reader can understand the basics of how ballistics work and vary among various calibers. There are numerous variations of the round such as hollow point and full metal jacket (FMJ) with even more manufacturers. The grain of the cartridge also plays a factor in ballistics. For example, a hollow point would have less penetration than an FMJ but would have more force at the point of impact (the knock-down power we've always heard about). Also, the grain of powder in the cartridge would affect penetration by having a higher velocity (speed) of the round. The average velocity of a .40 caliber round is 900-1450fps (feet per second) compared to the .45 caliber’s average velocity of 700-1150fps. One of the major factors regarding velocity is how much the round will slow down at greater distance from the barrel and the affect of gravity on the round. The greater the distance the round travels it slows down and begins a downward slope. This means at longer ranges the round will hit lower on the target than where you aimed. For practical applications, there is very little drop in a .40 caliber round at 25 yards.

The penetration of the .40 caliber round ranges from 9.8”-27” compared to a .45 caliber round that has a penetration of 11.3”-27”. The depth of penetration varies so greatly based on the type of round and the grain of the cartridge, but as you can see, in general the .45 does have deeper penetration.

The recoil of the .40 caliber is more than that of the .45 caliber primarily due to the smaller sized frame of the handgun itself. Generally speaking, the .40 caliber takes slightly longer to reacquire the target after a shot is made because of the recoil. From my experience as a firearms instructor shooters with smaller hands struggle more with follow-up shots because they are unable to have the optimal grip on the gun to reduce the recoil affect as much as possible. This leads to the follow-up shot not being as accurate. Continued practice can minimize the affects and improve accuracy. This is the most unpopular aspect of the .40 caliber.


Cost and Availability

The most important factor in choosing a caliber or firearm, for that matter, is accuracy. Accuracy is best obtained from practice. With that said, the second most important factor is cost and availability. If the round is not readily available then you will be subjected to the prices of a specialty dealer. Also, that dealer may not keep many rounds in stock due to the rarity and low demand. Every gun store/dealer I have dealt with is more than happy to order the rounds for you, but for me that is not convenient or cost affective especially with so many other options out there. The less rounds you have and the more expensive they are the less you will practice. This returns us to the most important factor, accuracy. The more you practice the better you will become and the more confidence you will have in yourself and your firearm.

The .40 caliber round is very common and can be found at any gun store, sports store, major department stores and online. I use Wal-Mart as my control group for ammo, as well as other products. Wal-Mart is not always the cheapest, but most people in the U.S. are close to Wal-Mart and since they have so many stores and can purchase in great bulk they can drive the cost down among other businesses. Online is also a great way to buy ammo in bulk and for reduced prices. Be careful that the online company is legit and provides quality service. Don't get scammed.

At my local Wal-Mart I can purchase a 100-count box of .40 caliber 165 grain FMJ for $32.36. That's around 34 cents each; much better than my .32 caliber revolver. In comparison, a 100-count box of .45 caliber 230 grain FMJ cost $37.97 which would be pushing 40 cents each after tax. Doesn't seem like much of a difference here, but on the range it goes fast.

A Very Common Caliber (For Good Reason)

The .40 caliber is new on the scene and has definitely made its presence known. This caliber has become one of the most common calibers among America's law enforcement and is seeing action with the military in special operations. There is nothing to show that the popularity trend is declining anytime soon so availability will not be an issue.

This caliber does pack a punch on both ends. I would certainly recommend the recoil rather than impact. I have enjoyed firing my .40 for years, but it does take practice to ensure solid control and follow up.

Whether you choose this caliber or another don't short change yourself. A pistol is an investment. Get your money's worth and have fun while doing it. Thank you and God bless you all.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2016 ericjperry