Your cart is currently empty!
The history and development of 25 ACP, known in Europe as 6.35mm Browning, begins with John Browning in mid 1904. The development of the cartridge appears to have mostly taken place in Belgium. Due to this, and its commercial nature, few records survive regarding it origins.
In 1901 Browning had created a blowback pistol design which he developed into a .32 caliber model for Colt and a 9mm model for FN. In 1903-1904, while Colt and FN were beginning production of their new pistols, Browning further adapted the design to be even smaller.
Colt was not initially interested in the small pistol, likely having seen it sometime in 1904. FN, however, saw the opportunity to bring an automatic into a market niche know as “revolver de poche”, or vest pocket pistol. FN would purchase patent rights in 1905 and begin sales of the pistol and it’s cartridge in 1906. Colt would follow suit and begin production in 1908.
The popularity of the “vest pocket pistol” is an odd story. It begins with the explosion of the bicycle as a common means of transportation. Early bicyclists, particularly those in Europe, found a need for defense against dogs. To fill this role small lightweight revolvers that could be carried on the torso in a vest pocket became extremely popular. Diminutive .22 caliber cartridges easily fulfilled the intended role, with many non-lethal bullet options available.
Due to the cheap availability and ease of concealment, it wasn’t long before people began carrying the tiny revolvers for self-defense. As the small revolvers began encroaching on the market dominated by larger caliber derringers, the cartridge options likewise expanded. Typical pistol cartridges ranged from .22-.32 caliber, with .22 rimfire being the most common.
Some insight into cartridge development by Browning can be inferred from the factory ledger of UMC. It records .30 caliber experimental cartridges ,using 60gr .288″ bullets, being produced in March of 1904, and .25 caliber experimental cartridges being produced in June of 1904. These records could imply that a .30 caliber cartridge was first used in Browning’s design, but for some reason it was found unsuitable. Further experimentation was also done during 1908 with a 7mm cartridge having the same case length and overall length as the .25, though it too would never be produced. The .25 caliber cartridge would become the 25 ACP, however, UMC did not begin full scale production until 1907, nearly a year after FN.
Early advertising listed the cartridge as firing a 50gr .251″ bullet at 820fps from the Browning pistol’s 2″ barrel. Today this is considered anemic by nearly every ballistic standard. However, compared to similarly sized cartridges of the time it was lethal, efficient, and reliable.