This cartridge was introduced in the United States in 1908 with the Browning-designed Colt-manufactured .25 Vest Pocket Automatic pistol. It had been introduced in Europe a few years earlier in the FN Baby Browning, which is practically identical to the Colt. The design of these two pistols has been copied by manufacturers all over the world. Dozens of different pistols have used this cartridge. American Arms, Beretta, Iver Johnson, Jennings, Lorcin, Phoenix Arms, Sundance, Taurus, Ortgies, Astra, Star, Kelt-Tech, Rohrbaugh, and Walther have all made pistols in this chambering. The .25 Automatic offers surprising velocity for such a small cartridge. However, delivered energy is quite modest. This, combined with the full metal jacketed bullet of the conventional load, adds up to very poor stopping or killing power on anything. Lighter, expanding bullets lack adequate penetration or delivered energy to suggest any significant improvement. The .25 Auto is not powerful enough for hunting anything but pests, nor is it adequate for serious self-defense. However, .25 Automatic pistols are popular because of their small size and low cost. Their principal usefulness might be as a threat, because no sane person wants to be shot. Winchester and Hornady recently offered hollow-point loads in an effort to improve terminal ballistics.
Editor's Note: This brief is an excerpt from Cartridges of the World 14th Edition.