AR-57

• Name — AR-57 • Origin — United States • Type — Semi-automatic rifle/pistol-caliber carbine (civilian variant) Personal defense weapon Submachine gun • Is Ranged — Yes • Service — 2019–present • Wars — Venezuelan crisis • Design Date — 2008–2016 • Manufacturer — Rhineland Arms (original), AR57 LLC • Unit Cost — US$1,099 • Production Date — 2008–present • Weight — 7.45 lb (AR-57 PDW) • Length — 30 in (AR-57 PDW) • Part Length — 16 in (AR-57 PDW) • Cartridge — FN 5.7×28mm • Feed — FN P90 detachable box magazines • Sights — M1913 Picatinny rail The AR-57, also known as the AR Five Seven, is available as either an upper receiver for the AR-15/M16 rifle or a complete rifle, firing 5.7×28mm rounds from standard FN P90 magazines. It was originally designed by Rhineland Arms but produced by AR57 LLC.

The AR-57 PDW upper is a new design on AR-15/M16 rifles, blending the AR-15/M16 lower with a lightweight, monolithic upper receiver system chambered in 5.7×28mm. This model is also sold as a complete rifle, supplied with two 50-round P90 magazines. The magazines mount horizontally on top of the front handguard, with brass ejecting through the magazine well. AR-15/M16-based STANAG magazines can be used to catch spent casings by taking out the feed lips, spring and follower. Sheet metal brass catchers can also be used on the AR-15/M16 lower. Various scopes and other accessories can be mounted on the picatinny rail. Unlike the standard AR-15 configuration which uses a gas-tube system, the AR-57 cycles via straight blowback. A fully automatic version exists and was marketed as a competitor to the P90 and other personal defense weapons. Suppressed versions are also available.

• Venezuela: Venezuelan soldiers who defected to Juan Guaidó were photographed using an AR-57 during the crisis in Venezuela in 2019.