TM  1-1520-240-10            4-2-1 SECTION  II.  ARMAMENT 4-2-1.  Armament Subsystems The armament subsystems, (fig. 4-2-1) are the M24, and M41 machine guns installed in the cabin door, cabin es- cape hatch, (M24) and on the ramp (M41). The two flex- ible 7.62 mm machine guns (M60D) (fig. 4-2-2) are free pointing but limited in traverse, elevation, and depression by cam surfaces, stops on the pintles, and pintle posts of the left and right mount assemblies (fig. 4-2-3). Spent cartridges are collected by an ejection control bag on the right side of the machine gun, and an ammunition can is on the left side (fig. 4-2-4). 4-2-2.  Machine Gun. The 7.62 machine gun (M60D) is a link-belt-fed gas-op- erated   air-cooled   automatic   weapon.   Refer   to   TM 9-1005-224-10. 4-2-3.  Mount Assemblies (M24). The   mount   assemblies   (fig.   4-2-5)   are   installed   on mounting  brackets  fastened  inside  the  helicopter  and secured with mounting pins. 4-2-4.  Machine Gun Controls. For information on the operation and maintenance of the M24   and   M42   machine   gun   systems,   refer   to   TM 9-1005-224-10 and 9-1005-262-13. WARNING To prevent injury to personnel, the cock- ing handle must be returned to the forward or locked position before firing. WARNING Pressing the trigger to release the bolt ac- complishes feeding and releasing of the firing   mechanism.   Unless   firing   is   in- tended,  make  sure  the  machine  gun  is cleared of cartridges before pressing the trigger. CAUTION To  prevent  damage  to  the  cartridge  tray when  no  ammunition  is  in  the  machine gun,  retard  the  forward  force  of  the  re- leased  bolt  by  manually  restraining  for- ward movement of the cocking handle. 4-2-5.  Mount   Assembly   Stops,   Cams,   Quick-Re- lease Pin, and Shock Cord (M24). The mount stops, cams, quick-release pin, and shock cord have the following functions: a. Maximum traverse (table 4-2-1) of the machine gun are controlled by stops on both sides of the cam on the pintle post. b. Maximum  elevation  and  depression  are  con- trolled by cam surfaces on the pintle. c. The quick-release pin (fig. 4-2-5 is attached by cable to the mount bracket of the mount and fastens the mount bracket to the rear bracket at the helicopter open- ing. d. The  shock  cord  (fig.  4-2-6)  is  fastened  to  the mount bracket and to the machine gun when stowed. 4-2-6.  Operation — Armament Subsystem M24. Operate  the  ARMAMENT  SUBSYSTEM  M24  as  de- scribed in the following paragraphs. 4-2-7.  Preflight Checks. The preflight check consists of the following: 1.   Machine Gun M60D — Check to make sure that  gun  is  thoroughly  cleaned  and  lubri- cated, operable, and secured on the pintle with the quick-release pin (fig. 4-2-9). 2.   Ejection control bag (fig. 4-2-7) — Installed and securely latched. 3.   Ammunition can (fig. 4-2-8) — Installed on machine gun and loaded. 4.   Safety — Push button to safe (S) position, aim  at  clear  area,  and  try  to  fire  the  un- loaded machine gun. 5.   Mount  —  Secured  and  checked  for  free pintle movement. 6.   Extra    ammunition    boxes    —    Properly stowed. 4-2-8.  Before Takeoff Check. 1.   Check the weapon safety is on — (S) posi- tion. 2.   Inspect the chamber to be sure it is clear. 3.   Close  the  cover  and  secure  the  machine gun in stowed position.