AK

is a common weapon naming prefix, and can refer to seven weapons in the Call of Duty series:
*AK-47 - An assault rifle featured in the Modern Warfare series and the Black Ops series, as well as in Call of Duty Online, Call of Duty: Advanced Warfare and Call of Duty: Mobile
*AK-74 - An assault rifle in Modern Warfare: Mobilized, Modern Warfare 3: Defiance and Call of Duty: Black Ops 6.
*AK-74u - A submachine gun/assault rifle in the Modern Warfare series and the Black Ops series, as well as in Call of Duty Online and Call of Duty: Mobile.
*AK117 - An assault rifle in Call of Duty Online and Call of Duty: Mobile.
*AKBP - A bullpup assault rifle in Call of Duty Online and Call of Duty: Mobile.
*AKBP Tech - Another bullpup assault rifle in Online.
*AK-12 - An assault rifle in Ghosts, Advanced Warfare and Modern Warfare.