The 9x23mm Winchester is a high-pressure semi-rimless pistol cartridge developed in 1996 for USPSA Open Division competition. Operating at 55,000 PSI, it drives a 125-grain bullet to ~1,450 fps from a 5-inch barrel, delivering .357 Magnum-class energy from a semi-automatic pistol while retaining 9mm bore diameter. Dimensionally similar to the obsolete 9mm Largo, it is not interchangeable due to far higher operating pressure.
Type: Pistol
Introduced: 1996, United States
Parent case: .38 Super
Standardization: SAAMI
Bullet diameter: 0.355" (9.02 mm)
Case length: 0.905" (22.99 mm)
Overall length: 1.169" (29.69 mm)
Max pressure: 65,000 PSI
Rim type: Semi-Rimless
Primer: Small Pistol
Typical twist rate: 1:10
Muzzle velocity: 1400–1450 fps
Muzzle energy: 539–583 ft-lbs
Effective range: 100 yd
Common bullet weights: 124, 125 gr
Primary use: competition_shooting, self_defense
Production status: Limited
Also known as: 9x23 Winchester · 9 x 23mm Win
History: Developed by Winchester in collaboration with the USPSA Open Division competitive shooting community. The goal was a 9mm-bore cartridge capable of meeting major power factor without the complexity of .38 Super tuning. The thick case web handles pressure safely in 1911-pattern Open guns. Despite logical design, the entrenched .38 Super Open community prevented widespread adoption, and the…
Notable firearms: Colt 1911 (competition), Springfield Armory custom 1911
Similar cartridges: .357 SIG, .38 Super, 9x19mm