Shotgun Ammo is not commonly found, though it is plentiful in gang hideouts. Shotgun Ammo is also found when taking out the Mexican stronghold with De Santa and when completing missions with Reyes as the shotgun is the preferred weapon for the Mexican Army. Disarming select enemies will force them to use their shotgun, giving access to ammo. As always, ammunition of all kinds can be found at any settlements' gunsmith, and should one not be present, check the general store.
In the Undead Overrun game mode, a second type of shotgun ammo - shotgun slugs - becomes available when a player opens a coffin. This type of ammunition is not available for shotguns outside of this game mode. Unlike standard shotgun ammo which consists of a shotgun shell filled with multiple pellets that spread out over range, shotgun slugs consists of a shotgun shell filled with a single large projectile. This makes shotguns effective out to much longer ranges at the expense of short range effectiveness.
The following weapons use Shotgun Ammo: