9x18

9x18, commonly written 9×18mm, refers to a pistol cartridge most widely associated with the 9×18mm Makarov (9×18mm PM). The designation indicates a bullet diameter near 9 millimeters and a case length of 18 millimeters. Standard ammunition typically uses a 92–95 grain (6.0–6.2 g) bullet, with muzzle velocities around 315–330 meters per second and muzzle energy roughly 320–360 joules.

History and development

The cartridge was designed in the late 1940s and early 1950s by Nikolay Makarov for the Soviet armed forces and was adopted in 1951 for use in the Makarov PM pistol and several related models. It provided reliable operation with moderate recoil in compact service pistols, serving as a backbone of Soviet and later post‑Soviet sidearms for decades.

Design and characteristics

9×18 is a rimless, straight‑case pistol cartridge. The round is shorter and less powerful than the 9×19mm Parabellum, contributing to lighter recoil and compact pistol designs. It is manufactured and used primarily in Eastern Bloc countries and nations that adopted Soviet‑style small‑frame pistols. The cartridge is not interchangeable with 9×19mm Parabellum; attempting to chamber or fire 9×18 rounds in a firearm designed for 9×19, or vice versa, is unsafe.

Usage and legacy

Today, the 9×18 Makarov remains in service in some countries and appears in surplus markets, especially for firearms based on or derived from the Makarov PM family. It is commonly encountered in historical discussions of Cold War era sidearms and in civilian markets where 9×18 ammunition is available. See also 9×19mm Parabellum for comparison.