AR57
AR57 LLC · Carbine · In Production · 2010
Also known as: AR Five Seven, AR-57
Overview
The AR57 (also marketed as the AR Five Seven) is an American semi-automatic carbine and drop-in upper receiver chambered in 5.7x28mm FN, designed to convert a standard AR-15/M16 lower receiver into a personal defense weapon. It feeds from top-mounted 50-round FN P90 magazines and operates by simple straight blowback rather than the gas-tube system of a conventional AR-15, ejecting spent brass downward through the magazine well. Manufactured by AR57 LLC of Kent, Washington, it is sold both as a complete rifle and as a stand-alone upper.
Specifications
| Weight (empty) | 3400 g (119.9 oz) |
| Overall Length | 762 mm (30.00") |
| Barrel Length | 406 mm (15.98") |
| Action Type | Blowback |
| Firing Mechanism | Hammer Fired |
| Trigger Type | Single Action |
| Magazine Capacity | 50 rounds |
| Magazine Type | Detachable Box |
| Muzzle Velocity | 716 m/s (2349 fps) |
| Muzzle Energy | 534 J (394 ft·lbf) |
| Effective Range | 100 m (109 yd) |
| Barrel Rifling | Right Hand |
| Frame Material | Aluminum |
| Barrel Material | Steel |
| Stock Material | Aluminum |
| Finish | Anodized |
Calibers
- 5.7x28mm FN · primary — also known as 5.7x28, FN 5.7
Features
- Firing modes: Semi Automatic
- Feed systems: Detachable Box Magazine
- Safety mechanisms: Manual Safety
- Features: Top Mounted Magazine, Picatinny Rail, Downward Ejection, Non Reciprocating Charging Handle, Ar15 Compatible Lower, Flash Suppressor
Variants
- AR57 ULT — Ultralight
Production
Production years: 2010-present
Produced by AR57 LLC of Kent, Washington; second-generation models introduced with lighter-profile barrels and M-LOK handguards
Origin
Country of origin: United States
Designer: AR57 LLC
Notes
The horizontal P90 magazine mounts atop the handguard and ejection occurs downward through the empty magazine well, giving the AR57 a distinctive ambidextrous, low-blast profile. A short-barreled pistol/PDW configuration is also offered.
Background
The AR57 was conceived as a way to bring the FN P90's high-capacity 5.7x28mm package to the ubiquitous AR-15 platform, letting owners reuse their existing lower receivers while feeding from the same translucent 50-round magazines that ride atop the iconic bullpup.