5.8×21mm

The 5.8×21mm cartridge is a Chinese armor-piercing firearm cartridge.

Description
The cartridge was designed for replacements of 7.62×25mm Tokarev–chambered small arms for the People's Liberation Army that would offer a wound as large as a standard 9×19mm Parabellum round. This round is offered in both a standard, and subsonic version. Both the QSZ-92 pistol and the QCW-05 Type 05 submachine gun are produced in this caliber as well as 9×19mm Parabellum.

The 5.8×21mm is slightly less powerful than similar Western rounds, like the 5.7×28mm and 4.6×30mm. It has a steel-cored 3 g bullet that has a muzzle velocity of 530 m/s and muzzle energy of 420 J from a submachine gun barrel. The round can penetrate 1.3 mm of helmet steel plate, and 50 mm of pine wood behind it, out to 100 meters.