TM-9-2350-311-10 M109 Operator's Manual for M109A2, M109A3, M109A4 and M109A5 Download
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TM 9-2350-311-10 2-12 PREPARATION FOR FIRING — CONTINUED 2-12.4 Pre-Fire Checks — Continued b. Cannon Tube 1 Cannon tube (7) must be dry and clear with no visible damage or foreign matter present. • If cannon is new or retubed, check the following before initial firing. If either step 2 or step 3 is not right, do not fire. The cannon may blow up, causing severe injury or death to personnel. Notify unit maintenance. • If major work has been done by direct support or general support maintenance, fire first round using 50 foot lanyard to prevent injury. • Do not fire without follower assembly. This will result in injury to personnel and damage to equipment. • High intensity hearing protection is required. Decibel levels from firing exceed safe levels for human hearing. Failure to wear hearing protection could result in hearing impairment. • The ventilation blower VENTILATOR BLOWER INTAKE switch must be turned to INTAKE during firing (para 2-17.3). CAUTION After a new M284 cannon assembly or a new torque key has been installed, a zone 6 charge must be fired to mate the torque key and the cannon tube. Failure to follow this procedure could result in equipment damage. 2 Rear face of cannon tube (7) must be flush with forward shoulder of breech ring (8). 3 Measure distance from rear face of cannon tube (7) to rear of breech ring (8). Distance cannot be more than five inches (12.7 cm). 2-200