.45 ACP
Heavy subsonic pistol and SMG cartridge
The .45 ACP is a heavy, slow-moving, large-diameter pistol cartridge designed by John Browning in 1904 for the M1911 pistol. Its subsonic 230 gr loading is inherently suited to suppressed weapons and submachine guns, and it remains in service with special operations and tactical police units where short-range terminal effect matters more than magazine capacity.
Full Specifications
Cartridge dimensions
| Designation | .45 ACP / .45 Auto / 11.43 × 23 mm |
|---|---|
| Case type | Rimless, straight |
| Bullet diameter | 11.5 mm (0.452 in) |
| Neck diameter | 12.0 mm (0.473 in) |
| Base diameter | 12.1 mm (0.476 in) |
| Rim diameter | 12.2 mm (0.480 in) |
| Case length | 22.8 mm (0.898 in) |
| Overall length | 32.4 mm (1.275 in) |
Ballistics
| 230 gr (15 g) FMJ | 255 m/s (835 ft/s), 483 J |
|---|---|
| 165 gr (11 g) JHP | 320 m/s (1,060 ft/s), 559 J |
| 185 gr (12 g) JHP +P | 370 m/s (1,200 ft/s), 803 J |
| Service reference | 230 gr round nose at approx. 250 m/s from a 127 mm barrel |
| Rifling twist | 406 mm (1 in 16 in) |
Standards & pressure
| SAAMI MAP | 21,000 psi (140 MPa) |
|---|---|
| C.I.P. Pmax | 19,000 psi (130 MPa) |
| Primer | Large pistol; small pistol with some makers |
Service context
| Introduced | Designed 1904 by John Browning, United States |
|---|---|
| Effective range | 50 m from a service pistol |
| Typical platforms | 1911-pattern pistols, .45 calibre submachine guns, suppressed weapons |
Dimensional, ballistic and pressure figures are the published C.I.P., NATO and SAAMI reference values for the .45 ACP cartridge (reference data). Steadfast production lots are proof tested and certified against the applicable standard. Product imagery is an in-house Steadfast studio visualisation and is indicative only; actual finish, headstamp and lot markings follow the applicable standard and the customer order.
