TM 9-2350-256-10 Table 2-1.  PMCS-Continued. Location Crewmember Not Fully Item Item to Mission No. Interval Check/ Procedure Capable if: Service 5 Before Caliber .50 Commander M2 Machine WARNING Gun Ensure machine gun is clear of ammo and barrel is free of obstructions. a. Check mounting of a. Machine gun machine gun in mount. or mount missing or unserviceable. b. Check headspace and b. Fault listed in timing.  For further "Not Fully PMCS refer to Mission TM 9-1005-213-10. Capable If" column of machine gun TM. 6 Before Carrier Driver/Commander Communi- cations a. Check radio equipment a. Fault listed in Equipment for proper condition.  Refer "Not Fully Radio to TM 11-5820-498-12 Mission and/or TM 11-5820-401-10-2, Capable If' as needed.   column of Refer to TM 11-5965-286-14 radio TM. for headset microphone. Radio will not transmit and receive. b. Check intercom system b. No intercom for proper operation. between commander and driver. 2-50