40mm Gun

Ammunition
The 40mm Gun uses 40mm shells, and holds 5 total clips by default. A maxed magazine can hold 56 clips; this means that the 40mm gun has a maximum ammunition capacity of 784 rounds.

Strategy
Though the weapon does indeed fire in Semi-Automatic mode, the 40mm gun is often best used as a medium range precision weapon in conjunction with its typical usage as a suppression weapon. Because the shell has a relatively low area of effect, the 40mm gun can be used for precision support or suppression, which is vitally important in hectic combat situations.

Real-Life Counterpart
Fans have speculated that the 40mm gun is likely based on the Bofors 40mm Gun, one of the most popular auto-cannons of World War II.