9×23mm explained

9×23mm may refer to one of the following pistol cartridges:

• 9×23mm Largo, introduced c. 1901
• 9×23mm Steyr, introduced c. 1911
• 9×23mm Winchester, introduced c. 1996
• .38 ACP, introduced c. 1900
• .38 Super, introduced c. 1929, which is a higher pressure loading of the .38 ACP pistol cartridge