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A handgun cartridge that is very popular for self-defense and is increasingly being used in police service pistols. Smith and Wesson developed the .40 S&W round off of the 10mm round in order to fill a large gap in stopping power between the 9mm and a .45 ACP. Unlike other rounds, .40 S&W bullets feature a flat tip as opposed to a smooth conical tip as seen in a 9mm. The bullets were designed this way so more surface contact will be made with the bullet's target. The .40 travels at very high velocities, giving the shooter quite a bit of recoil when the gun is fired. However, this additional velocity makes the bullet ideal for shooting through light cover such as car doors or windshields.

Data compiled from police shooting incidents put the .40 S&W at a 96% chance of stopping an attacker with one shot, proving it's value as a formidable defense cartridge. Cheaper than .45 ACP rounds, yet just as effective in getting the job done, the .40 S&W has seen great commercial success.
Guns chambered in .40 S&W are an excellent choice for self-defense.
.40 S&W by Ghost Dog August 3, 2007
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The round was developed by Smith & Wesson in 1990 by shortening the casing of the very powerful 10mm Auto. Even though it's only been around for nearly two decades, it has already achieved as much popularity in the US as the 9mm and .45 Auto, which have both been around for over a century.

Basically the round was created to solve a problem that never existed. It was developed to bridge a supposed "gap" between the 9mm and .45 Auto even though both rounds have substantial power as it is. The round appeals to a certain number of semi-auto enthusiasts who are dumb enough to believe that the 9mm is a pee-shooter, yet are too intimidated by the .45 Auto, which only has slightly more recoil. Still, it is a great round for self-defense.
Know-it-all: Don't buy a 9mm for self-defense, I've heard stories of 9mm bouncing off windshields and not being able to take down raging 6' 6" hoodlums on crack. Get a .40.

Me: And can you give me an example of a .40 S&W getting the job done?

Know-it-all: Ummm...no. But 9mm is still wimpy because I said so.
.40 S&W by WALTHERMAN March 25, 2010
Related Words
the slang for the .40 smith and wesson. a compromise between the notorious 9mm and the venerable 45acp. it packs a punch, as well as a large clip. a popular round for self-defense as well as police. it is similar is the 10mm, which is the same diameter but a long and thus more powerful case.
u ready for this?
are u kidding? i got my 40sw cocked and loaded
yeeeaw
40sw by James Hemma December 12, 2008
A small piece of information. Derived from the word ken, used often in the scottish language and is synonymous with knowledge.
Person 1: "Hey I don't get this shit. How do you solve this problem?"
Person 2: "I got that one. Give me some kenlets on this assignment and I'll help you w/ that one."
kenlet by Norma Y. October 8, 2005
Word of the Day on July 13, 2026

I mean I guess bro

a word of expression to when you give up on comprehending someone's words of ignorance, stupidity, absurdity or are too exhausted to formulate a proper response.

Commonly seen in TikTok comment sections in replies to lazy attempts at humor, overconfidentally incorrect statement, or an over-the-top comment or when someone completely misses the mark on something.
"actually... incorrect statement, hope this helps!"
"I mean I guess bro"
Word of the Day on July 12, 2026

abandonware 

n. software that is no longer sold or supported by the original publisher / developer, often found as free downloads on the internet because it cannot be obtained elsewhere. Not legal, but often seen as morally acceptable because the company that made it is no longer selling the title, nor releasing it as freeware, therefore abandonware is "keeping the game alive", so to speak.
Doom II is not abandonware because id still sells it, while The Incredible Machine is not sold, therefore is abandonware.
abandonware by Spoom October 24, 2003
Word of the Day on July 11, 2026

Foot prisons 

Socks. Annoying, sweat-causing, non-barefoot enducing, everyday socks.
The first thing I do when I take off my shoes, is rip off the foot prisons I had to wear inside them. That's why I prefer flip flops, even in winter!
Foot prisons by Jackalope Hunter December 13, 2022
Word of the Day on July 10, 2026