.357 sig

The .357 SIG pistol cartridge is the child of the famous German firearms manufacturer SIG/SAUER, in cooperation with the American ammunition manufacturer Federal Cartridge.

History

Based on the .40 S&W pistol cartridge, SIG reversed Georg Lugers logic when he went from the 7.65 mm Luger cartridge to the 9 mm Luger cartridge. The .357 SIG cartridge is a bottleneck version of the .40 S&W cartridge, thus any .40 S&W pistol can be converted to .357 SIG, if it is built in a strong enough fashion, by replacing the barrel and recoil spring. Some pistols with especially strong recoil springs can accept either cartridge with a barrel change only. Magazines will freely interchange between the two cartridges. .357 SIG barrel kits have allowed this cartridge to continue to gain in popularity among handgun owners. The idea was to offer at least the level of performance of +P 9 mm Luger ammunition and to be close to the performance of the famous 125-grain (8.1 g) .357 Magnum cartridge. The recoil of the .357 SIG cartridge is strong, but not as harsh as the 10 mm Auto.

Handloading warning

Because the .357 SIG is based on the .40 S&W case, novice handloaders may be tempted to form .40 S&W cases into .357 SIG brass. This MUST NOT be done. Although the two cases are identical in rim diameter, using the .40 S&W case to form .357 SIG cases will result in a case that is approximately 0.020 in (5.1 mm) too short. Unlike most bottlenecked cartridges, the .357 SIG headspaces on the case mouth; cartridges that are too short can result in serious malfunctions of the guns in which they are used, possibly leading to serious injury.

Performance

The .357 SIG offers a very flat trajectory like the 10 mm Auto. Combined with expanding bullets, it has very good stopping power. Its drawbacks are its harsh treatment of pistols that use it, which wear quickly, and its strong overpenetration when full metal jacket bullets are used. The .357 SIG, like the .357 Magnum, is well suited for the use of bullets that can defeat body armor. The .357 SIG is a great police and special forces cartridge, useful against dangerous animals; however, it does not quite reach the performance of the venerable .357 Magnum. Offsetting this slight disadvantage in performance is the fact that pistols carry considerably more ammunition than revolvers.

Muzzle velocity

8.1 g (125 gr) full metal jacket: 411 m/s (1350 ft/s)

Usage

The Sig Sauer P229 in .357 SIG is the standard issue firearm carried by agents of the United States Secret Service.

Synonyms

.357 Auto