Difference Between Similar Terms and Objects

Difference Between 9mm and .40 Caliber

9mm vs .40 Caliber

If you want to start owning and shooting guns, you’ve probably wondered on the type of gun to start with. Two common options are 9mm and 0.40 calibers. The main difference between 9mm and 0.40 calibers is the size of the bullet. Converting 9mm to inches, you get roughly 0.35, significantly smaller than the 0.4 inch diameter of the .40 caliber.

Because the .40 caliber has a larger diameter, it also has greater mass, which directly correlates to the stopping power of the bullet. It will deliver more energy to the target, disabling him with fewer bullets. The lesser weight of the 9mm bullet means that less energy is delivered to the target. The .40 caliber is better in self-defense situations where you need to disable the assailant as quickly as possible to prevent him from getting a shot off.

But between the 9mm and the .40 caliber, the 9mm is much better suited for beginners mainly for two reasons. The first is the smaller amount of recoil produced by round. Because the .40 caliber has a larger and heavier bullet, there is also more gunpowder there to propel bullet. Recoil can mess the aim of a shooter and will often cause the next shoot to be off target. Using the 9mm lets the shooter get accustomed to the recoil and adjust accordingly before moving on to bigger rounds. The second factor is the cost of the bullets. 9mm bullets are considerably cheaper than .40 caliber bullets. So you can purchase more with a given budget and shoot more downrange. Practicing more hones your skill as a shooter as there is no better teacher than experience.

Choosing the right firearm to own and use is still largely subjective. Larger people may not feel as much recoil with the .40 caliber than someone with a smaller stature. Or a certain firearm may feel better than another. The best thing to do is to try each firearm that you are interested in and decide on which one you like best.


  1. The .40 caliber has a bigger and heavier bullet than the 9mm
  2. The .40 caliber has better stopping power than the 9mm
  3. The 9mm is better suited for beginners than the .40 caliber
  4. The .40 caliber has more recoil than the 9mm
  5. The .40 caliber bullets are typically more expensive than 9mm bullets

Sharing is caring!

Search DifferenceBetween.net :

Email This Post Email This Post : If you like this article or our site. Please spread the word. Share it with your friends/family.


  1. You are comparing apples and oranges. You might as well compare a .25 Auto with a .38 Special. WHY bother? They are different.

  2. Thank you for this article. It was very informative!

  3. This article appears to be written with limited personal experience or research.
    AS a former Marine, and current patrol Division Commander at my police department, I can tell you that the 9mm is essentially just as effective as .40 cal and in my opinion, better in several ways.

    The 9mm, with less recoil, is proven to be more accurate when staying on target with multiple shots. Shot placement to critical areas of the body is far more important than the size of the bullet.

    The same size or model handgun in 9mm will generally hold 2/3 more rounds.

    Advances in ammunition (bullets and propellants) have made 9mm rounds more effective,

    There is a reason why the FBI and the majority of federal agencies have switched back to 9mm from .40 cal.

    The author states the 9mm is better suited for beginners??
    I would ask the author to tell that to a Marine or a navy seal.

    If you really feel the need to for more “stopping power” then got to .45 or 10MM. If you know ballistics, you would know that .40 call is basically 10mm lite.

    .40 caliber handguns are great for home defense. I carry one every day at work. My choice for off duty carry my personal weapon is 9mm.

    This topic is very much a matter of opinion and either caliber will serve you well for defense. I’ll posts few links here that can provide further information.



  4. Well explained Rich. Quick question…..
    I’m not a novice shooter but certainly not anywhere near an expert. (Probably just above novice) I currently own a Sig P226 in 9mm and shoot it pretty well.
    I’m looking for more of a carry pistol and have been going back and forth from a 40 cal to a 9mm M&P Shield. Can’t decide which one to get. I keep thinking if I get the 40 cal I can always purchase a 9mm barel and kind of have the best of both worlds. Or do I just get it in 9mm and call it a day. I do stock a good amount of 9mm ammo. Or as you said maybe just jump to a 45? I know some say stick with one consistent caliber. Very undecided?

  5. This article is correct. I have both and like them both. 9mm for cc and the 40 for everything else. You can’t go wrong with either one. The 9 is a little cheaper to shoot and is good for people defense (and females had a hard time with the 10mm and 40 so the FBI went with 9mm). I use a Double Tap hardcast with the 40 in the woods. Practice makes perfect (simple as that).

  6. I am 6’1 and 210 pounds. I have shot the Walther PPS in 9mm and .40. If I could only fire one round in a life or death situation, I would fire the .40. The difference in recoil is minimal to me.

Leave a Response

Please note: comment moderation is enabled and may delay your comment. There is no need to resubmit your comment.

Articles on DifferenceBetween.net are general information, and are not intended to substitute for professional advice. The information is "AS IS", "WITH ALL FAULTS". User assumes all risk of use, damage, or injury. You agree that we have no liability for any damages.

See more about : ,
Protected by Copyscape Plagiarism Finder