Shotgun (attachment)

The Shotgun is a weapon attachment in Call of Duty: Modern Warfare 2. It is an under-barrel pump-action shotgun known as the Masterkey, based on the Remington 870MCS developed originally for the M16 assault rifle. It is attached under the barrel of a weapon in a similar manner to grenade launchers.

In-game
In Multiplayer it is unlocked for Assault Rifles by getting 20 Kills with the mounted grenade launcher. It is pump-action with a four round magazine, and a capacity of 20 shells. If put onto a weapon with limited close quarters effectiveness like FAL, FAMAS or M16A4, or a weapon that has a small magazine, like the SCAR-H, the custom class becomes more versatile while still allowing for a secondary weapon. This attachment is not often used by players and can allow the user to surprise enemies. It is also faster to switch to this attachment than it is to switch to any secondary weapon other than a handgun. Unlike most secondary shotguns which fire eight pellets per shot, the Masterkey fires only six pellets. Players should notice that the crosshairs grow larger when the player is moving, unlike other shotguns. This is unusual because none of the other shotguns lose hip accuracy while moving. This shotgun has by far the longest range of all of the shotguns, with its pellets traveling more than double the range of the Model 1887. However, at such ranges it will take multiple shots to kill a target, making it fairly ineffective. The Masterkey benefits greatly from both Stopping Power and Steady Aim.

Trivia

 * It is most likely intended to be a KAC Masterkey, although other companies such as Ciener and Serbu produce similar items.
 * If the FAL is used with a Silencer and the Masterkey, the Shotgun will not produce a red dot on the enemy's mini-map, although it's firing sound is not affected.
 * The Masterkey is primarily designed for door breaching. It was not intended for anti-personnel use.
 * The Masterkey was designed to attach to the M16 and M4 series of rifles, and is not compatible with other rifles, such as the TAR-21 and AK-47.
 * Every time the player switches to the Shotgun attachment, the player's character cycles the action. In reality, this would eject a round, wasting ammunition.
 * A good tactic is to use the Masterkey Shotgun on any assault rifle, when secondary weapon is a launcher, especially the Stinger, because the player will lose usefulness in close combat as the Stinger as a secondary means that a shotgun/machine pistol cannot be used.
 * It is a good idea to attach this to a medium-ranged weapon, so you can use this in close range, saving your rifle ammo.
 * This is often contrasted to the M203 as the grenade launcher provides long-range suppressive abilities, while the Shotgun provides additional close range firepower.
 * When used along with a Heartbeat Sensor the majority of the Sensor's screen is hidden from the player's field of view, but still beeps.
 * In Campaign mode the Shotgun has a capacity of 7 rounds. In Multiplayer, it holds 4 rounds; this was ostensibly done to preserve game balance.
 * If this attachment is used in conjunction with FMJ, FMJ will affect the Shotgun.
 * The Masterkey and the SPAS-12 are the only pump action shotguns in multiplayer.