4 mm Flobert Short

Its origins date back to the 1840s, when Karl Fedor Horrmann decided to use percussion caps to propel small-caliber projectiles. It was not until the late 1800s and early 1900s that gunsmiths Fischer, Lorenz Dieter, and Carl Stiegele—working independently of one another—each created their own systems for firing round projectiles powered by percussion caps. Since metal machining techniques of that era lacked precision, Carl Stiegele devised a sizing chart in 1903 ranging from number 1 to number 24, with number 1 corresponding to a 4.04 mm shot and number 24 to a 5.45 mm caliber. Based on this chart, Carl Stiegele manufactured his barrels, subsequently stamping each with the corresponding shot number. The chart was adopted by other manufacturers in 1910, and the current standard was modified in 1912, wherein #1 represents 4.00 mm and #24 represents 5.15 mm.^[4][5][6]

Currently, Zimmerstutzen remains a traditional competitive discipline in which the use of standard 4mm Randz Kurz and 4mm Randz Lang ammunition—featuring their respective 7.7-grain projectiles (formerly #7, now #9)—is permitted. Alternatively—given that vintage rifles are still utilized in this discipline—one may opt to use a projectile-less version of the aforementioned cartridges and separately insert a shot pellet of up to 4.75 mm (formerly #12, now #16); this practice is similar to the munisalva rounds, popular in Mexico.^{[4][5][7][8][9][10][11][12]}