ACR

The Remington ACR (Adaptive Combat Rifle) is a contemporary multi-cartridge, multi barrel-length assault rifle system that has been designed as a replacement for the M4 Carbine. The gun (in game) is a variant of the updated version of the Masada Adaptive Combat Weapon System, which was made by the US firearms company Magpul Industries prior to a licensing agreement with both Bushmaster (who makes the civilian version) and Remington (who produces the military version). The weapon borrows traits from other firearms, most notably the ambidextrous operating handle in a forward position, similar to the SCAR-H, as well as SCAR-style modular construction. It was designed from the ground up by Magpul, using only the front sight post, barrel and the fire control mechanism of the M16, while incorporating a folding stock and full length rails. Its internal components are heavily influenced by the AR-18, a piston-operated alternative to the AR-15 developed by Armalite. The ACR is intended to fire with 5.56x45mm NATO (likely the one used in game), 6.8x42mm Remington SPC, 6.5x39mm Grendel, and 7.62x39mm ammunition. The ACR uses a quick-change barrel system that allows it to change calibers quickly, and it can use STANAG (5.56, 6.5 or 6.8mm) or AK-47 type (7.62x39mm) magazines, with the AK magazines needing a change to the lower receiver. The Remington ACR is unlocked at level 48 in multiplayer.

Modern Warfare 2 uses the 14.5-inch barrel configuration. The ACR is only used by Task Force 141 and Shadow Company. It is also commonly used by Ghost and Roach, and is their starting weapon in most TF141 missions in the game.

Singleplayer
The ACR is first available to the player while running The Pit in the mission S.S.D.D.. It is also used in the mission Cliffhanger, with a Red Dot Sight, Silencer, Heartbeat Sensor, and a unique arctic camouflage. A version with ACOG and Grenade Launcher is used in Takedown, while another version featuring Holographic Sight and Grenade Launcher is used in Loose Ends. A version with a unique matte black finish and the same attachments as found in Cliffhanger can also be found in the mission Just Like Old Times.

Multiplayer
In multiplayer, the weapon is unlocked at Level 48. The ACR is similar to the M4A1 but trades a higher accuracy for a lower rate of fire and virtually no recoil. It carries 30 rounds in its magazine, deals 30-20 damage per shot, and has a fire rate of 750 RPM. The ACR, although it bounces when firing, has zero recoil as it resets perfectly before the next shot which makes it ideal for medium and long range combat. Its moderately low damage per second makes it somewhat weak in close quarters combat compared to other automatic weapons, making it a good candidate for use with the Masterkey Shotgun.

As a versatile weapon, most Perks and Attachments work well with the ACR, especially Stopping power which allows it to fill a variety of roles. The ACR is primarily used at long ranges and excels in medium-large sized and large maps with long lines of sight such as Wasteland, Afghan, Highrise, Derail, Estate and Bailout. Unlike most weapons, the ACR suffers no noticeable increase in recoil or sway from the use of ACOG. The ACR consumes ammo fairly quickly, but its complete lack of recoil means that wasting ammo due to missed shots is usually not an issue. Moreover, it should be noted that the ACR is one of the most effective weapons in the game for reload cancelling; the player doesn't even need to wait until the magazine is fully inserted into the rifle before ammo is replenished.

In terms of damage output per second, the ACR's low damage and moderate rate of fire make it one of the lowest damage output weapons in the game. The ACR makes up for this at medium and long range with its practically nonexistent recoil. Its accuracy during fully automatic fire allows it to kill faster than weapons where burst-firing would be necessary.

Weapon Attachments

 * Grenade Launcher
 * Shotgun
 * Red Dot Sight
 * EOTech Holographic Weapon Sight
 * Silencer
 * Heartbeat Sensor
 * ACOG Scope
 * Thermal Scope
 * FMJ
 * Extended Mags

Trivia

 * On Infinity Ward's website, the ACR was voted the favorite assault rifle in Modern Warfare 2.
 * Unlike the multiplayer version, the campaign ACR has noticeable vertical recoil and high damage per round.


 * In Just Like Old Times there are three ACRs that are in the same configuration as the ACR from Cliffhanger, possessing Red Dot Sights, Silencers, and Heartbeat Sensors. Both of these ACRs have unique camouflages, with the one from Cliffhanger using a variant of Arctic camo while the ones in Just Like Old Times are completely black.


 * In Just Like Old Times players can have two ACRs with the same attatchment layout, due to camo's counting as difference.


 * The ACR appears larger than any other assault rifle when seen from 3rd Person.


 * Although a bolt release is present on the ACR, the in-game reload animation still shows the charging handle being used as a way to load a new round to the gun's chamber.


 * Heartbeat Sensors appear slightly smaller on this gun than any other assault rifle.


 * The serial number of the ACR in Modern Warfare 2 is 0091436.
 * Captain Price sometimes uses the black ACR in the mission Just Like Old Times.

Video
thumb|400px|left|ACR gameplay