Before firing the M60E3, what maintenance step is crucial?

Inspecting the mechanical condition of the M60E3 before firing is crucial because it ensures that the weapon is in good working order and capable of functioning safely and effectively. This step involves checking for any signs of wear, damage, or malfunction that could impair the weapon's operation. Proper inspection includes assessing the barrel, bolt, and feed mechanism, as well as confirming that all components are securely in place. Any issues identified during this inspection could lead to failures during operation, potentially jeopardizing the safety of the operator and the effectiveness of the squad's firepower.

While other maintenance aspects such as applying oil, checking ammunition, or confirming the functionality of a range finder are important, they come after ensuring that the weapon itself is in a proper mechanical state to operate. Performing a thorough mechanical inspection stands as the foundational step that ensures all other maintenance procedures are meaningful; a gun that is mechanically unsound will not fire accurately or safely, thus making this step the priority before firing the M60E3.