The .40 S&W


The .40 Smith & Wesson is a success story that almost defies logic, but as the "New Age" folks say: "The stars were all aligned" in its favour. There had been a few attempts to come up with a cartridge for autoloading pistols that had more power than the 9mm Parabellum but more magazine capacity than the .45 ACP. A .40 calibre (or 10mm for the metric-friendly folks) bullet was seen as a possibility, and back in the days shortly before World War I John Browning was working on an improved pistol design that borrowed a lot from his now-classic 1911 --- but old John had some significant improvements in mind. One of these was to chamber the new pistol in a .40 calibre (or 10mm) cartridge and use a magazine with two staggered rows of cartridges rather than one linear row as in his 1911. Browning was working for Fabrique Nationale (FN) in Liège, Belgium in those years and FN was backing this project with a view to marketing the new Browning pistol to the French Army. So the French had significant say in what was actually done. This project eventually became the famous Browning P-35, or "Hi-Power" after it was finished by Dieudonné Saive after Browning's death. With the clouds of WW I on the horizon, the French didn't want to switch to an entirely new calibre; logistics would have been an nightmare. So the P-35 was made in 9mm Parabellum, but not in time for use in "The Great War." So interest in a .40 calibre autopistol round dropped to a slow simmer at best until the 1970s or '80s.

In the 1970s a couple of folks at Guns & Ammo magazine (possibly including Col. Jeff Cooper) jumped on the slowly-rolling .40 calibre bandwagon. They used the available .40 calibre 180 grain bullets that were made for the old .38-40 Winchester round (yes, it IS a .40 calibre round -- see the entry about the .38-40 for the history if you are interested) and they cut-down .224 Weatherby Magnum rifle brass for the cases. The ".40 G&A Magnum" as it was dubbed performed well in modified Browning P-35 pistols (180 grain bullet at 1250 fps is pretty darned good) but it remained a wildcat round -- and a difficult and expensive one to produce at that. Interest was underwhelming.

About this time, or possibly in the early 1980s, another .40 calibre pistol round was developed. It was called "The Centimeter" cartridge and it preceded the 10mm Auto, even though you will see it referred to as a "shortened 10mm." Again, .38-40 bullets were used, but this time with a simpler case that was essentially a cut-down .30 Remington rifle cartridge case. Unfortunately .30 Remington was nearly "unobtanium" at this time. This round had potential, but the timing was wrong. The 10mm Auto was introduced and undermined the Centimeter round. This was in spite of the 10mm's own teething problems.

Then came the infamous Miami shootout of 1986. The FBI concluded after a lengthy investigation that they needed a pistol with more "stopping power" --- rightly or wrongly. The Bureau adopted the 10mm Auto giving the round a new lease on life after the Bren Ten pistols faded into history. Things seemed OK until some FBI Agents complained about the recoil of the 10mm and qualifying scores dropped as well. The big 10mm required more practice to shoot well than agents were giving it. So the FBI had the ammo makers back off on the powder charge to produce a round that came to be known as the "10mm Lite." Somebody at Smith & Wesson noticed that with the lesser amount of powder, the cartridge case didn't have to be so big. In fact, the powder charge could fit into a .40 calibre case that was not significantly longer than a 9mm Parabellum case and those cartridges would fit and function in pistols designed for the 9mm Parabellum with fairly minor changes to the pistol. Thus was born the .40 S&W and it became one of the most popular police cartridges in America practically overnight.

The .40 S&W has always gathered its share of complaints for being "neither fish nor fowl" as it has lower power than the .45 ACP and less magazine capacity than the 9mm Parabellum. It has been called the ".40 Short and Weak" by detractors, but that is not really true. Surely it isn't a full-power 10mm but it is by no means "weak." Whether or not these complaints are justified is a matter of opinion. As of 2015 many police agencies are re-thinking the .40 and returning to the 9mm. The pendulum of history swings and returns.

This was designed as a police and self-defense cartridge and it does that job rather well. It's not a good choice for hunting with a handgun, even if the game laws allow it where you happen to be. Some shooters find the recoil from the .40 S&W to be too "snappy" as they put it. I have not noticed that. But then if I opt for a .40 calibre autopistol round, it will be the 10mm Auto -- but that's just me.


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