Glock G31

About the Glock G31

The Glock G31 is a semi-automatic pistol chambered in .357 SIG, produced by Glock Ges.m.b.H. since 1997. This Austrian-manufactured firearm reflects the engineering traditions and quality standards of its country of origin, designed to meet the demands of both civilian and professional users in a competitive global marketplace. Featuring a 15-round magazine capacity, this pistol offers generous firepower for duty use and home defense. The striker-fired action provides a consistent trigger pull for every shot, simplifying training and reducing the manual of arms - a design philosophy that has become the dominant paradigm in modern defensive handguns. The 4.5-inch barrel provides an excellent balance between sight radius and portability, making it equally suitable for duty carry and recreational shooting. Weighing 660g (23.3 oz) empty, this firearm strikes a practical balance between manageable carry weight and sufficient mass to moderate felt recoil during shooting. The polymer frame construction reduces weight while providing a textured, ergonomic grip surface designed for secure handling in all conditions. This firearm represents its manufacturer's commitment to delivering a well-engineered, reliable product that serves the needs of discerning shooters seeking quality, accuracy, and dependable performance from a proven platform.

The .357 SIG cartridge and the Glock 31 were born from a specific law enforcement need: replicating the legendary stopping power of the .357 Magnum revolver in a modern semi-automatic with high capacity. The Federal Air Marshal Service notably adopted .357 SIG Glocks, valuing the round's ability to incapacitate threats through aircraft seat material while minimizing over-penetration risk. At its peak, an estimated 20% of U.S. law enforcement agencies used .357 SIG, with many selecting the G31 as their duty weapon.

Glock G31 specifications

The G31 is dimensionally identical to the Glock 22 (.40 S&W) and can be converted between .357 SIG and .40 S&W with a simple barrel swap, as the .357 SIG is a necked-down .40 S&W case. This interchangeability made the .357 SIG Glocks attractive to agencies that could stock both calibers. The .357 SIG's bottleneck design provides extremely reliable feeding. Despite excellent ballistic performance, the .357 SIG has declined in popularity as many agencies transitioned back to 9mm following the FBI's 2014 ammunition study. The G31 has been discontinued by Glock.