AMMO

The AMMO attachment slot covers ammunition choices and magazine attachments for your weapon. These may impact ballistics or magsize.

FMJ
Unlocked at Weapon Level.

FMJ, or Full Metal Jacket, is a bullet that deals enhanced damage to killstreaks, penetrates walls better, loses less damage from wall penetration, but has worse direct damage to players.

Subsonic
Unlocked at Weapon Level. "Shots are slow, but nobody will know where they're coming from"

Subsonic ammunition will remove the tracer effect and the bullet crack, but slow your muzzle velocity.

Extended Magazine
Unlocked at Weapon Level. "50% bigger magazine capacity"

Increases ammunition capacity by 50%, and decreases reload and mobility slightly.

Will show as X Round Magazine, whatever 50% more is, thus a 30r weapon would have the 45 Round Magazine, while a 20r weapon would have the 30 Round Magazine.

Drum Magazine
Unlocked at Weapon Level.

Increases ammunition capacity by 100%, minor mobility/reload decrease. Same naming scheme as the Ex. Mags.

Hollow Points
Unlocked at Weapon Level 50.

Increases direct damage to players and decreases damage to streaks; wall penetration decreased.