.380 ACP

.380 ACP
A .380 ACP pistol cartridge by Sellier & Bellot
Type	Pistol
Place of origin	United States
Production history
Designer	John Browning
Designed	1908
Manufacturer	Colt's Manufacturing Company
Produced	1908–present
Specifications
Case type	Rimless, straight
Bullet diameter	.355 in (9.0 mm)
Land diameter	.348 in (8.8 mm)
Neck diameter	.373 in (9.5 mm)
Base diameter	.374 in (9.5 mm)
Rim diameter	.374 in (9.5 mm)
Rim thickness	.045 in (1.1 mm)
Case length	.680 in (17.3 mm)
Overall length	.984 in (25.0 mm)
Case capacity	11.8 grains h20
Primer type	Small pistol
Maximum pressure	21,500 psi (148 MPa)
Ballistic performance
Bullet mass/type Velocity Energy 90 gr (6 g) Buffalo JHP 1,025 ft/s (312 m/s) 210 ft⋅lbf (280 J) 95 gr (6 g) Federal FMJ 980 ft/s (300 m/s) 203 ft⋅lbf (275 J) 45 gr (3 g) RBCD TFSP 1,835 ft/s (559 m/s) 337 ft⋅lbf (457 J) 100 gr (6 g) Buffalo +P HC-FN 1,160 ft/s (350 m/s) 299 ft⋅lbf (405 J) 85 gr (6 g) Norma MHP 1,280 ft/s (390 m/s) 309 ft⋅lbf (419 J)
Test barrel length: 3.75 inches (95.3 mm) Source(s): Federal Cartridge[1] Buffalo Bore Ammunition[2] RBCD Performance Plus Ammunition[3] Norma Ammunition[4]

The .380 ACP (Automatic Colt Pistol, also known as .380 Auto, .380 Automatic, or 9×17mm), is a rimless, straight-walled pistol cartridge that was developed by firearms designer John Moses Browning. The cartridge headspaces on the mouth of the case.^[5] It was introduced in 1908 by Colt, for use in its new Colt Model 1903 Pocket Hammerless semi-automatic, and has been a popular self-defense cartridge ever since, seeing wide use in numerous handguns (typically smaller weapons). Other names for .380 ACP include .380 Auto, 9×17mm, 9mm Browning, 9mm Corto, 9mm Kurz, 9mm Short, and 9mm Browning Court (which is the C.I.P. designation). It should not be confused with .38 ACP. The .380 ACP does not strictly conform to cartridge naming conventions, named after the diameter of the bullet, as the actual bullet diameter of the .380 ACP is .355 inches.