The Remington ACR (Adaptive Combat Rifle), previously known as the Magpul Masada before Bushmaster and Remington took over production, is an assault rifle developed initially and proposed for the future replacement of the M16 and M4 family of assault rifles. The ACR uses the standard 5.56×45mm NATO round but is also intended to be modifiable to employ the 6.5mm Grendel, 6.8mm Remington SPC, .308 Winchester and the Russian 7.62×39mm M43 rounds. Similar to other weapons such as the HK416 and the SCAR family of rifles, it uses a piston instead of the direct impingement of the M4/M16 series of weapons.
In the Battlefield series, the ACR is referred to as the ACW-R (Adaptive Combat Weapon - Rifle) and appears in five games. It fires the 6.5×39mm Grendel round in Battlefield 3 and 5.56×45mm NATO in all other appearances.