.40 vs 9mm: Caliber Comparison

.40 vs 9mm: Caliber Comparison

January 18, 2024 By Posted in Blogs

When it comes to the world of firearms and ammunition, caliber matters, and selecting the right caliber for your needs is crucial. But choosing from a multitude of calibers can often be an intimidating task, especially when you’re weighing options such as the .40 calibers and the 9mm. These two calibers, created by different ammunition giants, have sparked numerous debates amongst firearm enthusiasts and law enforcement agencies worldwide.

Our discussion today will revolve around varying factors including bullet weight, muzzle velocity, law enforcement preferences, shot placement, and more. The aim is to equip you with enough information to make an informed decision between the two calibers, whether you use your firearm for self-defense, sport, or to protect and serve.

The .40 Caliber: An Overview

Let’s start with a thorough exploration of the .40 caliber. Developed with law enforcement needs in mind, the .40 Smith & Wesson (S&W) was meant to fill the gap between the heavy .45 ACP and the lightweight 9mm cartridges. This heavier bullet, often weighing an average of 180 grains, provided a blend of power, control, and size that law enforcement agencies had been seeking.

The .40 Caliber: An Overview


The .40 caliber S&W loads showcased impressive performance with higher pressure and larger bullet diameter, making it an ideal choice for self defense and law enforcement situations. The punch it packs in terms of terminal performance, the way it produces a sizable wound track, and its stopping power, is where the .40 caliber shines. This caliber was designed with a focus on effective shot placement, particularly to vital organs, which is a necessary characteristic in self defense and law enforcement contexts.

The other significant aspect of the .40 caliber that people talk about is its kinetic energy when it leaves the barrel, also known as muzzle energy. While the subject can be complex, to put it simply, higher muzzle energy can result in greater damage potential. As such, the heavier .40 caliber bullet carries significant muzzle energy, making it widely favored among shooters and police departments alike for its terminal ballistics.


However, every element carries its own set of pros and cons, and the .40 S&W is no exception. Although it packs more power, it’s also associated with stouter recoil. While this isn’t inherently a negative thing, less experienced shooters might find it slightly more challenging to manage this recoil. The capacity of the magazine is usually less than that of the 9mm due to the difference in bullet size. However, the preference for the .40 S&W cartridge continues to hold strong among shooter circles who prioritize power balance and effective terminal performance over magazine capacity and lesser recoil.

Ultimately, the .40 caliber’s ability to offer a balance of power and control makes it an excellent option for both self-defense needs and law enforcement applications.

The 9mm: An Overview

Now, we’ll focus on the other dominant player in this comparison – the 9mm. A brainchild of Georg Luger, this popular caliber was introduced over a century ago. Known for its versatility and wide range of applications, the 9mm has seen widespread usage among casual shooters, self-defenders, and law enforcement agencies alike.

The 9mm: An Overview


The 9mm offers a lighter bullet, usually around 115-147 grains. Its higher velocity and lower pressure give it an edge over the .40 S&W. 9mm rounds have proved to be reliable over the years, and their performance, when assessed in terms of kinetic energy and muzzle velocity, testifies to their popularity.


Of course, the context in which the 9mm is used matters significantly- from self-defense scenarios to law enforcement agency use. For law enforcement, the larger magazine capacity is often an appealing factor given the unpredictable nature of their duties. Similarly, in self-defense scenarios, the higher capacity can offer reassurance and an added layer of security.


However, no coin is without its flip side. Despite its numerous pros, the 9mm faces criticism for its smaller bullet diameter, which could potentially result in less kinetic energy transferred to the target. This directly ties into the ongoing debate about stopping power and which caliber brings more to the table.


Yet, it’s hard to overlook the benefits of the 9mm. Its less recoil allows for quicker follow-up shots, and typically, the ammunition is more affordable and widely available. Add in the higher magazine capacity and it’s easy to see how the 9mm has cultivated such a vast following among firearm enthusiasts.

It’s clear that the 9mm carries distinct advantages and few drawbacks, just as the .40 caliber does. But how do these two stack up against each other when compared head to head?

Comparing .40 vs 9mm – Which Caliber is Right for You?

We’ve dissected the .40 caliber and 9mm on their own. Now, it is time to cross-examine these two and confront the question many firearm users find themselves asking – .40 vs 9mm, which caliber is right for me?

Comparing .40 vs 9mm – Which Caliber is Right for You?


When we consider effectiveness in self defense and law enforcement, much comes down to shot placement and the ability to neutralize a threat efficiently. The .40 caliber, with its higher muzzle energy, bigger bullet, and superb terminal performance, does offer a distinct advantage. However, the 9mm, with its higher capacity and lower pressure, allows for quicker and more accurate follow-up shots – a valuable trait when seconds count.


Another key determinant is price and availability. Typically, 9 mm ammo is more affordable and more readily available. However, while this may weigh into your decision, it’s essential to remember that the quality and performance of the ammunition are the most important aspects, regardless of application.


In recent years, there has been a significant shift in law enforcement agencies towards 9mm, driven by advancements in 9mm ammunition technology and the capacity advantage it holds. Yet, there are still many departments and self-defense advocates who swear by the .40 caliber for the extra punch and power balance it brings to the table.


In terms of terminal performance, both the .40 caliber and the 9mm have demonstrated effectiveness. With modern hollow point ammunition, both calibers can deliver the damage needed to stop threats effectively.

The Verdict and How Berry’s Bullets Can Help

At the end of the day, it boils down to personal preference, intended use, and what you feel most comfortable shooting. Whether it’s the increased stopping power and heavier bullet of a .40 caliber or the higher magazine capacity and less recoil of the 9mm, the choice is truly personal.

At Berry’s Bullets, we offer a wide array of superior plated bullets for both .40 S&W and 9mm. We’re committed to supplying you with the highest quality products, no matter your choice of caliber. Our family-based business is founded and operated by firearm enthusiasts dedicated to offering exceptional quality, friendly customer service, and product bases proudly made in the USA.