AA-12

The  (Auto-Assault 12) is an American Automatic combat shotgun that appears in Call of Duty Modern Warfare 2 and Call of Duty: Modern Warfare: Mobilized.

Singleplayer
The AA-12 is rarely seen in the campaign. It is however, the main weapon for a few Special Ops missions.

Multiplayer
The AA-12 is unlocked at Level 18 in Modern Warfare 2's multiplayer.

The AA-12 is a unique shotgun, as it is fully automatic and utilizes a magazine. It has an 8-shell magazine capacity, which is doubled when the Extended Magazines attachment is used, which balances the weapon's power and speed. The AA-12 empties its magazine far more quickly (400 RPM in multiplayer) 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 the Sleight of Hand Perk is utilized. Since it uses magazines rather than individual shells, it is the fastest empty loading shotgun in the game.

In multiplayer, the AA-12 has only one extra magazine, so it is wise to use it sparingly, unless the Scavenger perk is used. It has moderate recoil unless firing full-auto, and very poor range, even when compared with other shotguns. This means that players using the weapon will have to get fairly close to enemies to use it effectively. However this trait makes it a highly useful weapon for clearing rooms, or areas full of enemies. Using Extended Mags will increase the capacity to 16 shells, allowing prolonged fire. Using Extended Mags in conjunction with Scavenger (as otherwise, with Extended Mags, you have no extra magazines) can make it a highly useful weapon, and has made some players use it as a "primary" weapon. Using a silencer with this weapon makes it almost completely useless, as it shortens the range to roughly 5-10 yards, which means that the user must get incredibly close to enemies to actually be able to hit them. The AA-12 is very effective on Sabotage or Demolition matches as it can clear out a room with ease due to its rate of fire.

Players almost never use a Silencer for this weapon due to it's low range already without the Silencer.

It is also notable that with the Grip attachment, the AA-12's switch time is noticeably quicker than without the grip. Though this can be remedied by double tapping the 'switch weapon' button (Triangle on PS3, Y on Xbox 360 and 1 or 2 [Default] on PC) quickly to make the switch time quicker.

It is highly recommended to hip fire AA-12, since it is hard (and usually unnecessary) to trace enemies with the iron sights, and because of the fact, that shotguns are more accurate this way (Steady Aim makes this even more effective). If used as a main weapon, one should choose Scavenger or Sleight of Hand, Stopping Power (not necessary) and Steady Aim or if the user prefers it, Commando, in case of the shells running out. It is also a good idea to use the AA-12 in conjunction with Cold Blooded and/or SitRep Pro, as well as Scavenger Pro, for a good under-the-radar class.

Weapon Attachments

 * Red Dot Sight
 * Heartbeat Sensor (Spec Ops only)
 * Silencer
 * Grip
 * FMJ
 * Holographic Sight
 * Extended Magazines

Modern Warfare: Mobilized
The AA-12 appears as one of the two shotguns available in Modern Warfare: Mobilized, the other being the SPAS-12. Though the AA-12 seems similar to the AA-12 in Modern Warfare 2, there many differences between the two. First of all, the AA-12 is a frequent starting weapon in the later levels of campaign mode; is used in the U.S. Marine missions most frequently. It also comes with a 32-round drum magazine by default, much greater damage per shell, a greater one-shot kill range, near infinite pellet range, and a much lower and controllable rate of fire than the Modern Warfare 2 version.

Singleplayer
In single player, the AA-12 is a versatile weapon, having a near infinite range, high damage, and a large 32 shell drum magazine. The extremely high range allows the player to make a kill at any distance, though the pellets will spread apart as the distance between the player and the target increases, negating the one-shot kill effect and decreasing accuracy considerably. Combined with the high damage, large shell capacity and near infinite range, one can fire multiple shells to make a kill at long range if needed. As mentioned before, the AA-12 is found in the later levels of campaign mode as a starting weapon, more specifically, in the levels Training, Closing In, To the Rig, and Oil Rig Confrontation.

Mulitplayer
In multiplayer the AA-12 is the second weapon to be unlocked for the Coalition multiplayer faction, taking 150 kills with the Coalition faction to earn.

Trivia

 * The AA-12 has a different reload when the Heartbeat Sensor is equipped (only available in spec ops); 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.
 * In the Spec Ops mission, Acceptable Losses, players start off with the AA-12 with three different attachments, the Red Dot Sight, Silencer and a Heartbeat Sensor. This is impossible in multiplayer.
 * The AA-12 has different rates of fire in singleplayer and multiplayer mode.

Video
thumb|left|300px|AA-12 Montage/Gameplay