AA-12

The AA-12 (Atchisson Auto Assault-12) is a select fire shotgun considered to be the first shotgun directly designed for military and law enforcement use. It fires at 350 RPM (400 RPM ingame), and accepts an 8 round detachable box magazine, a 20 or 32 round drum. Its biggest rival is the versatile, and extremely popular Russian Saiga 12KS-K select fire shotgun.

Call of Duty: Modern Warfare 2
The AA-12 is a unique shotgun because it's fully automatic. It has an 8-round magazine capacity, which is doubled when Extended Magazines is attached, which balances the weapon's power and speed, but may have a capacity of 70 extra shells, and fires full-auto. The AA-12 empties its magazine far more quickly (650 RPM singleplayer) than it reloads as the magazine needs to fit onto the magazine support, and then slide up into the magazine well, though this is slightly offset when using the Sleight of Hand Perk. Since it uses magazines rather than individual shells, it is the fastest loading shotgun in the game. TIP: When using the AA-12, try firing it in bursts, and not to hold down the trigger unless completely surrounded in close quarters. Firing full automatic introduces significant vertical recoil, even with the grip.

In multiplayer, the AA-12 has only one extra magazine, so use it sparingly (unless you have Scavenger to keep your ammo count up.) It also has moderate recoil and poor range compared to other shotguns, so players will have to get fairly close to use it effectively. Using Extended Mags increases the shotgun's magazine to 16 rounds, allowing the user to fire it for longer. This makes it a very good weapon for clearing rooms full of enemies. Many people have suggested it has the worst range of all the shotguns, having to be near point blank range to cause any harm, and its fire rate is so high you have to keep some control when firing the weapon. It is recommended that a user uses Scavenger with the AA-12, as its ammo runs out after two magazines, or one if the player is using Extended Mags.The AA-12 is commonly used instead of a primary weapon - a lot of players have the Riot Shield for back protection - for its incredible power and fire rate. Many people who use this weapon utilize the perks Scavenger Pro, Stopping Power and Steady Aim. When using this weapon one should either choose Scavenger or Extended Mags as having just one of them is enough to maintain ammo.

The AA-12 is a good weapon on multiplayer when entering rooms in order to clear out snipers or campers because of its automatic abilities. This weapon is at its best with the extended mags attachment as it needs constant reloading. Using a silencer is almost completely useless as the range is shortened to about five yards, about the length of a Commando knife swing.

Call of Duty: Modern Warfare: Mobilized
In game, the AA-12 is used in the U.S. Marine missions, and can be found in the weapons room in the mission Training. It comes with a 32-round drum magazine by default, more damage and slightly slower automatic fire than the console version. It is the second to last weapon to be unlocked for the USMC/SAS multiplayer faction.

Trivia

 * The AA-12 fires faster, has much more range, and lower recoil in singleplayer than in multiplayer.


 * The AA-12 has a different reload when the Heartbeat Sensor is equipped (only available in single player); the empty magazine will actually be thrown away when reloading, instead of disappearing off-screen as is the case with other attachments. The Heartbeat Sensor is also very visible even when aiming down the sight, a characteristic that is shared with multiple weapons including the TAR-21 and the L86 LSW.


 * The AA-12 in singleplayer fires at about 2 times the fire rate as its real life counterpart. In game, it fires at 550-650 RPM, and reality, at 350 RPM. In multiplayer the fire rate is far more realistic.


 * The AA-12's extended magazine attachment in-game doubles its ammo capacity to 16 shells. Strangely, as with most "extended mags", there has been no record of a 16 shell magazine ever made for the AA-12.


 * Some AA-12's in multiplayer, If seen laying on the ground, are equipped with a Heartbeat sensor. Even though the heartbeat sensor is not available in multiplayer. However when you pick up the AA-12, the heartbeat sensor is gone.


 * In real life, the AA-12, as well as many other shotguns, is capable of firing 12 gauge, specially designed grenade rounds.


 * In the Spec Ops mission, Acceptable Losses, you start off with the AA-12 with three different attachtments, the Red dot sight, silencer and a heartbeat sensor. This is impossible in multiplayer.