9×21mm

9×21mm
Type Pistol
Place of origin  Israel
Production history
Designer Israel Military Industries
Specifications
Parent case 9×19mm Parabellum
Case type Rimless, straight
Bullet diameter 9.03 mm (0.356 in)
Neck diameter 9.63 mm (0.379 in)
Base diameter 9.93 mm (0.391 in)
Rim diameter 9.96 mm (0.392 in)
Rim thickness 1.27 mm (0.050 in)
Case length 21.15 mm (0.833 in)
Overall length 29.75 mm (1.171 in)
Case capacity 1.01 cm³ (16 gr H2O)
Rifling twist 254 mm (1 in 10 in)
Primer type Small pistol
Maximum pressure 235.00 MPa (34,084 psi)
Ballistic performance
Bullet weight/type Velocity Energy
7.45 g (115.0 gr) FMJ 390 m/s (1,300 ft/s) 570 J
8.00 g (123.5 gr) FMJ 360 m/s (1,200 ft/s) 518 J
Source(s): C.I.P.[1]

The 9×21mm pistol cartridge (also known as the 9×21mm IMI or 9 mm IMI) was designed by Israel Military Industries for those markets where military service cartridges, like the 9×19mm Parabellum, are banned by law for civilian use, such as Italy and Mexico.

Contents

History

Based on the 9×19mm Parabellum cartridge, the casing was lengthened from 19 to 21 mm (0.75 to 0.83 in). The bullet sits slightly deeper, which results in almost the same overall length as the 9×19mm Parabellum cartridge.

Cartridge dimensions

The 9×21mm has 1.01 ml (15.5 grains H2O) cartridge case capacity.

9×21mm maximum C.I.P. cartridge dimensions.[1] All sizes in millimeters (mm).

The common rifling twist rate for this cartridge is 254 mm (1 in 10 in), 4 grooves, Ø lands = 8.79 mm, Ø grooves = 9.03 mm, land width = 3.80 mm and the primer type is small pistol.

According to the official C.I.P. (Commission Internationale Permanente pour l'épreuve des armes à feu portatives) guidelines, the 9×21mm case can handle up to 235 MPa (34,100 psi) piezo pressure. In C.I.P. regulated countries every pistol cartridge combo has to be proofed at 130% of this maximum C.I.P. pressure to certify for sale to consumers.

Notes

As it is a rimless round, the 9×21mm is used in USPSA/IPSC competition in Open class firearms. The reasoning is that the semi-rimmed case will not lock together in a double-column magazine, causing a malfunction, whereas an improperly built .38 Super firearm can, as the rimmed cases can lock together in the magazine, causing a jam. As other .38 Super–based .38 Super Auto rimless cases became available, the 9×21mm decreased in popularity in the United States for competition use, but it is still widely used in the rest of the world.

Synonyms

See also

References