Secondary Weapons are weapons that take up the secondary weapon slot in the inventory. Originally, secondary weapons provided players with the ability to quickly swap weapons in case one ran out of ammo, but recent installments give the player more flexibility in customizing their class to fulfill more roles in combat.

Call of Duty and Call of Duty: United Offensive permitted the player to carry two primary weapons and a pistol sidearm. Beginning with Call of Duty 2, players could only carry two weapons of any kind. Since the release of Call of Duty: Modern Warfare 2, the secondary weapon category provides multiple types of weapons instead of only handguns. Types of secondary weapons include:

• Launchers, such as the RPG-7 or SMAW
• Shotguns, such as the Ranger or M1014 (Modern Warfare 2)
• Handguns, such as the Five Seven or Desert Eagle
• Machine Pistols, such as the MP9 or G18 (Modern Warfare 2 and Modern Warfare 3)
• Special Weapons, such as the Crossbow or Ballistic Knife (Black Ops and Black Ops II)

The One Man Army perk takes up the secondary weapon slot.

To use the secondary, the player simply has to swap from the primary weapon using the Swap Weapons button. The speed of the swap ranges from each classification of Secondary Weapon, Pistols being the fastest and Launchers being the slowest. Each Secondary also has its own amount of Attachments (excluding Launchers and Specials) and usage, such as the G18 being used in typical Sniper Classes in case an unwelcome guest decides to attempt an ambush, or the AA-12 can be used to quickly make haste and wipe a room out to capture an objective.

Secondary weapons do not have challenges that require other attachments, like getting the Holographic Sight from sixty Red Dot Sight kills, nor do they have mastery. This makes them a little less useful when wanting to get experience, but they are still very useful.

OverviewEdit

• Pistols can be used as a quick finisher as these Secondaries have the fastest swap time out of the four Secondary Weapon groups.
• Machine Pistols are frequently used in Close Quarters Combat to midrange, as they have high damage or rate of fire but limited range and high recoil.
• Shotguns are used as a quick blow to enemies at close range, and even earn Double to Multi-kills, as it's tough to survive a blow from a Striker or SPAS-12 without the aid of the Deathstreak Painkiller. However, their effectiveness rapidly falls over distance, making them most useful inside buildings, or on smaller maps.
• Launchers are either a type of Splash Damage Secondary, or an Anti-Air Secondary; The RPG-7, AT-4, and Thumper make use of a large explosive radius while the Stinger and Javelin are the Anti-Air Launchers (the Javelin is also capable of locking onto ground targets albeit taking longer to get there than the RPG-7 and Thumper).
• Secondary weapons in Black Ops II are the only secondary weapons that accept weapon camouflage in multiplayer.This was going to be changed in Modern Warfare 3, however this was cut before official release.
• Swapping to a secondary doesn't increase movement speed, so if the player wants to use a weapon such as a handgun with Tactical Knife for speed knifing, it is suggested to use a high maneuverability Primary Weapon, such as an SMG. An exception to this is Black Ops and Black Ops II, in which weapons only affect movement speed it is being used by the player.
• In Call of Duty: Black Ops II, the player can choose to remove a secondary weapon from their class. Upon switching weapons with no secondary weapon selected, the Combat Knife will be used.