What happens when the trigger of the MK19 machine gun is depressed?

When the trigger of the MK19 machine gun is depressed, the receiver sear is triggered, which allows the firing mechanism to engage. This action serves a critical role in the weapon's operation, as it is responsible for releasing the firing pin to strike the primer of the round. As a result, this initiates the firing sequence, leading to the discharge of ammunition.

The operation of the MK19 is designed so that once the sear is triggered, it facilitates the entire cycle of automatic fire, which includes the chambering of the next round from the feed system. Understanding this mechanism is essential for ensuring proper handling and operation of the weapon during training and combat situations.