In Baldur's Gate, it has the smallest variety of ammunition, with only three choices of bullet; Bullet, Bullet +1, and Bullet +2. The Enhanced Edition add a variety of elemental damage dealing bullets.
Baldur's Gate II adds the enchanted Bullet +3 and Bullet +4, as well as the Sunstone Bullet. Baldur's Gate II: Throne of Bhaal also adds the Bag of Plenty which supplies an unlimited amount of Bullet +1, and can be upgraded to supply Bullet +2.
|“||Slings have existed since the beginning of recorded history. The basic sling consists of a leather or fabric strap with a pouch for holding the missile. The weapon is held by both ends of the strap and twirled around the wielder's head. When top speed is attained, the missile is launched by releasing one of the strap's ends.||”|