.25 ACP

The .25 ACP (Automatic Colt Pistol) (6.35x16mmSR) centerfire pistol cartridge is a semi-rimmed, straight-walled pistol cartridge designed by John Browning in 1906.

Design
The cartridge was designed for early blowback pistols that lacked a breech locking mechanism. The cartridge is of semi-rimmed design meaning that the rim protrudes slightly beyond the diameter of the base of the cartridge. A recessed extractor groove allows an extractor to grab the cartridge reliably. It is the smallest centerfire pistol round in production, and is commonly chambered in small, so-called "vest pocket" pistols. A line of revolvers produced by the German firm Decker were chambered for this cartridge. However it is probably most popular due to use in the Colt Model 1908 Vest Pocket and the Raven MP-25.

Performance
The use of the .25 ACP allows for a very compact lightweight gun, but the cartridge is short ranged with regards to power, putting it in the same class as the .22 LR rimfire cartridge. Although the .22 is slightly more powerful when fired from equal length short barrels, the .25 ACP is viewed by many as a better choice for personal defense due to its more reliable semi-rimmed centerfire case design. Manufacturers have loaded commercial hollow point bullets to higher velocities than the standard 50 grain FMJ load. Both rounds certainly pose an effective psychological threat against attackers not armed with a firearm. Firearms chambered for the .25 ACP cartridge are somewhat uncommon. Frequently, low-cost firearms are manufactured in this caliber.

Synonyms

 * 25 Auto
 * .25 Auto
 * 6.35 mm
 * 6.35 mm Browning
 * 6.35x16mmSR

Categories
Cartridge:handguns