Luger pistol
Luger's work on the Borchardt design evolved into the Luger pistol, which was first patented in 1898 and chambered in 7.65×21mm Parabellum. Demand from Germany for a larger caliber in their military sidearm led Luger to develop the 9×19 mm Parabellum cartridge for the eventual P08 pistol. This was achieved by removing the bottleneck shape of the 7.65×21mm Parabellum case, resulting in a tapered rimless cartridge encasing a bullet that was 9 mm in diameter.