The ACR (Adaptive Combat Rifle) is an automatic assault rifle which is now in service with the Polish Army. It was developed by Magpul Industries and is currently being manufactured by Bushmaster and Remington. It features an interchangeable barrel system, which enables the rifle to shoot 5.56x45mm NATO, 6.8x43mm Remington SPC, and .223 Remington cartridges. offering different barrel lengths, from 10.5″ (27 cm) to 18″ (46 cm). For the 6.8mm ammunition also the bolt carrier assembly must be replaced along with the barrel. The ACR has an adjustable, piston-driven, gas-operated reloading system, with rotating bolt. It is fitted with an ambidextrous charging handle and a fire selector lever. The rifle barrel is cold hammer-forged and has a melonite coating. This weapon has an effective range of 500 m, with a muzzle velocity of 990 m/s, using 30-round Magpul magazines. It is an accurate and dependable rifle, equipped with a system of rails for attaching different accessories, such as optical scope sight, forward handgrip, and tactical flashlight. The Remington ACR has seen combat action in Afghanistan with the Polish Special forces.