The .40 Smith & Wesson

By Chuck Hawks

.40 S&W
Illustration courtesy of Hornady Mfg. Co.

The Winchester designed .40 Smith & Wesson was introduced in 1990. The basic idea was to duplicate the ballistics of the 10mm FBI load (the 10mm Lite) in a cartridge that would feed in medium frame autoloaders designed for the popular 9x19. S&W realized that for police or self-defense purposes the large powder capacity of the 10mm Auto was wasted and the drawbacks of a large frame pistol (required for the 10mm) could be avoided if the new cartridge could be made small enough to work in medium frame (9x19mm) pistols.

The new cartridge was named the .40 Smith & Wesson. It uses the exact same .400" diameter bullets as the 10mm Auto. By reducing the powder space to only that needed to duplicate the 10mm Lite police load, the case was held to the same overall length as the 9x19. The .40 uses a true straight case. It is not tapered for feed reliability like the 9x19 case. The SAAMI mean maximum pressure is 35,000 psi.

The .40 S&W successfully met all of its design parameters and was an immediate success. It has become the most popular police cartridge in the US. Beretta, Browning, CZ, Glock, H-K, Kahr, Ruger, SIG, S&W, Taurus, Walther and just about everyone else offers service style autoloaders in .40 S&W. All of the major ammunition companies load .40 S&W cartridges. The sales of reloading dies in the caliber are also strong.

The cartridge was helped along by passage of the ill-advised "Brady Bill," which mandated 10 round magazines in the U.S. Pistols that formerly held 15 rounds of 9mm or 10 rounds of .40 were limited to 10 round magazines in either caliber. The 9x19 lost its advantage in firepower because of the artificial influence of the Brady Bill. A lot of shooters no doubt figured that if they are limited to 10 rounds, they might as well have the biggest 10 rounds that will fit into the gun. In most cases, that was the .40 S&W. and .40 gun sales soared.

Factory loads are offered with 135, 155, 165, and 180 grain bullets. The popular Federal Hydra-Shok 155 grain and Remington Golden Saber 165 grain bullets in .40 S&W are both running an excellent 94% one shot stops, according to the ongoing study by Marshall and Sanow.

The published ballistics of the 165 grain Remington Golden Saber (JHP) load shows a muzzle velocity of 1150 fps and muzzle energy of 485 ft. lbs. The mid-range rise is 1" over 50 yards, and 4" over 100 yards. This is typical of the popular 155-165 grain factory loads.

Reloaders have plenty of components from which to choose. The fifth edition of the Nosler Reloading Guide shows that 6.8 grains of WSF powder can drive their 135 grain JHP bullet to a MV of 1072 fps, and 7.8 grains of WSF can drive the same bullet to a MV of 1242 fps. These loads used Winchester cases, WSP primers and were chronographed in a 4" pistol barrel.

Naturally, increased energy means increased recoil and the .40 kicks more than the 9x19. It also has noticeably increased muzzle blast. Both are less than with the .357 Magnum, however, and the .40s larger and more capable brother the 10mm Auto.

If there is a bad rap on the .40 S&W it seems to be that accuracy in most pistols is below the average of the 9x19, 10mm, or .45 ACP. Accuracy is normally acceptable for a pistol to be used at typical self-defense range (less than 10 yards), but the relatively large groups delivered by many .40 pistols at only 25 yards makes long range shooting with these pistols problematical. The .40 S&W would probably not be the best choice for someone who might have to defend himself or herself in the great outdoors, where the 10mm Auto is the King of Autoloading Pistol Cartridges.

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Copyright 2001, 2016 by Chuck Hawks. All rights reserved.