Which condition triggers the hot barrel procedure for the M240B?

• A. Long continuous burst
• B. 200 rounds in 2 minutes
• C. TL or VC deems it a hot barrel
• D. 15 minutes since last deemed a hot barrel

Answer: (C)

Barrel overheating prompts the hot barrel procedure when the TL or VC judges the barrel is too hot to continue firing safely. Heat buildup varies with rate of fire, ambient temperature, ammunition type, and barrel wear, so there isn’t a universal round count or time threshold. The trigger is the leader’s determination that continuing to fire could risk cook-off or damage, based on cues like the barrel being too hot to touch, muzzle glow, or visible heat distortion. When that assessment is made, the crew switches to a spare barrel to keep firing safely. The other options don’t fit because a fixed burst length or a set number of rounds isn’t a reliable trigger, and waiting a fixed time since the last hot-barrel deeming isn’t how the procedure is determined.