7.65×21mm Parabellum

7.65×21mm Parabellum
7.65mm Parabellum, Swiss manufacture (Thun, 1973)
Type	Pistol
Place of origin	German Empire
Service history
In service	1898–1949
Used by	Germany, Switzerland, Finland
Wars	World War I-present
Production history
Designer	Georg Luger and Hugo Borchardt
Designed	1898
Manufacturer	Deutsche Waffen und Munitionsfabriken
Specifications
Parent case	7.65×25mm Borchardt
Case type	Rimless, bottleneck
Bullet diameter	7.85 mm (0.309 in)
Neck diameter	8.43 mm (0.332 in)
Base diameter	9.93 mm (0.391 in)
Rim diameter	9.98 mm (0.393 in)
Rim thickness	1.22 mm (0.048 in)
Case length	21.59 mm (0.850 in)
Overall length	29.85 mm (1.175 in)
Case capacity	0.93 cm3 (14.4 gr H2O)
Rifling twist	275 mm (1 in 10.83 in)
Primer type	Berdan or Boxer Small pistol
Maximum pressure	235.00 MPa (34,084 psi)
Ballistic performance
Bullet mass/type Velocity Energy 6.03 g (93 gr) FMJ 370 m/s (1,200 ft/s) 412 J (304 ft·lbf)
Source(s): Modern Firearms & Ammunition, Pistol Ammunition

The 7.65×21mm Parabellum (designated as the 7,65 Parabellum by the C.I.P. and also known as .30 Luger and 7.65mm Luger) is a pistol cartridge that was introduced in 1898 by German arms manufacturer Deutsche Waffen und Munitionsfabriken (DWM) for their new Pistol Parabellum. The primary designers were firearms designers Georg Luger and Hugo Borchardt, who developed the round from the earlier 7.65×25mm Borchardt while working at DWM.

In 1897, the C-93 Borchardt pistol was submitted for testing to the Swiss Military Trials Committee. The Committee found the Borchardt too heavy and unwieldy to serve as a military sidearm. Georg Luger was tasked by DWM with improving upon the Borchardt pistol. He developed the 7.65×21mm Parabellum cartridge from the 7.65×25mm Borchardt. By shortening the cartridge case, Luger was able to design a narrower grip, and the toggle action required a shorter stroke than in the original Borchardt design. A transitional Borchardt-Luger model in the new caliber was submitted to the Swiss commission in 1898. After further improvements, the final result became the DWM Pistole-Parabellum ("Luger pistol"). The loading for the new cartridge was standardized and mass production began in 1900–1901 in DWM's factory in Karlsruhe, Germany.

Around 1903, a separate load was developed for Parabellum carbines, with approximately 20% more powder (increased from the standard 0.32–0.35 g to 0.4 g) and a blackened cartridge case. This carbine load was manufactured until sometime after World War I.

Since its introduction, 7.65×21mm Parabellum ammunition has been manufactured in several countries for both domestic use and for export, including Germany, Switzerland, Finland, France, Portugal, Brazil, the United Kingdom and the United States.