

The campaign is mainly played out from the perspective of two characters, a Task Force 141 member named Yuri and a Delta Force operator named Derek "Frost" Westbrook. As the US repels the Russian invasion the former members of Task Force 141, including Captain Price and "Soap" MacTavish, begin the hunt for terrorist mastermind Makarov as he sets into motion his ultimate plan to begin a third world war.

The story continues from Call of Duty: Modern Warfare 2, with the former members of Task Force 141 disavowed and hunted and the United States under siege from the Russian military. The game has variously been developed by Infinity Ward, Sledgehammer Games and Raven Software, and was published by Activision in 2011 for the PC, PS3 and Xbox 360. This gun is a semi-automatic sniper rifle with very high penetration.Call of Duty: Modern Warfare 3 (also known as CoD:MW3 or MW3) is the eighth installment in the Call of Duty series, and the third main entry in the Modern Warfare sub-franchise. Its closest rival is the CheyTac Intervention, they are very similar weapons, in which they both have the same rate of fire and are both very powerful. The Barrett is most praised for its ability to deliver one hit kills with a high rate of fire. However, the ability to fire so fast can be an advantage in close quarters when there is no time to switch to a secondary and the player is forced to fire their sniper rifle from the hip. This requires great concentration, as inexperienced players tend to fire too fast. This problem is easily mitigated by simply slowing the rate of fire and only firing when the recoil has settled. Firing too quickly makes the Barrett difficult to use, as it will be extremely difficult for the shooter to see what they are shooting at. The Barrett is capable of firing faster than its sight can settle. In multiplayer, the Barrett is unlocked at Level 4 (Private First Class). Unlike the version found in the earlier level, this one can be carried and used freely, just like in multiplayer. Another is found in Loose Ends in one of the basement rooms of the safe house. However the weapon is immobile, similar to the way it was in One Shot, One Kill, including the scalable zoom function and unlimited ammo. This version has a thermal scope instead of a sniper scope. On one occasion, it is found in the mission Of Their Own Accord in the room where the player must destroy the enemy vehicles at long range. 50 cal can be found twice in the single player campaign. In addition, it is the first sniper rifle available to the player, while in Call of Duty 4 it is the last.

The only notable change from Call of Duty 4 is that sniper rifles now have full mobility, the same as SMGs. 50cal is almost completely unchanged, with the exception of new attachments and a redesigned scope.
