What is the first step when removing an M240's barrel?

The first step when removing an M240's barrel is to depress and hold the barrel locking latch in. This is crucial because the barrel is designed with a locking mechanism that secures it in place to prevent accidental dislodging during operation or maintenance. By pressing and holding the barrel locking latch, you disengage this mechanism, allowing you to freely rotate and remove the barrel.

Without this step, any attempt to turn or unscrew the barrel would be ineffective, as the locking mechanism would still be engaged. This ensures that the operator can safely and efficiently remove the barrel while minimizing the risk of damaging the weapon or causing safety hazards. Once the latch is held in, other steps such as turning the barrel counterclockwise can then be performed to complete the removal.