5mm Bergmann

5mm Bergmann
Type	Pistol
Place of origin	German Empire
Production history
Designer	Bergmann
Designed	1894
Produced	1896–1900
Specifications
Bullet diameter	.2 in (5.1 mm)
Ballistic performance
Bullet mass/type Velocity Energy 35 gr (2 g) FMJ 580 ft/s (180 m/s) 26 ft⋅lbf (35 J)
Source(s): "Textbook of Automatic Pistols"

The 5mm Bergmann is an unusual centerfire cartridge produced for very early self-loading pocket pistols. The case is steeply conical and headspaces on the conical case walls. Early versions (sometimes called the 5 mm Bergmann Rimless) were made without any rim or extraction groove; and relied upon blow-back for expulsion of the fired case from the chamber. Later Bergmann pistols provided an extractor requiring a groove which produced a semi-rimmed case. The long bullet was inadequately stabilized and tended to tumble in flight.