TM-9-2350-311-10 M109 Operator's Manual for M109A2, M109A3, M109A4 and M109A5 Download
Page 261 of 775
TM 9--2350--311--10 Change 6 2--163 2--12 PREPARATION FOR FIRING — CONTINUED 2--12.1 Pre-Firing Emplacement — Continued c. Emplacing Infinity Aiming Reference M1A1/M1A2 Collimator — Continued (f) Ensure azimuth adjustment is in center of the traversing capabilities by operating the azimuth adjustment knob (56). NOTE M1A2 only has an on/off switch for the light sequence. (g) Turn switch (56.1) ON. (h) Loosen azimuth adjustment clamping knob (57). Sighting down front and rear sights (58), rough lay M1A1/M1A2 collimator (21) on M117/M117A2 panoramic telescope (36) objective lens. Tighten azimuth adjustment clamping knob. Adjust M1A1/M1A2 collimator elevation as required and tighten elevation adjustment clamping knob (55). (i) Loosen cross-level clamping knob (59). Rotate M1A1/M1A2 collimator (21) until bubble in cross-level vial (60) is centered. Tighten cross-level clamping knob. 2 Sighting through M117/M117A2 panoramic telescope (36), gunner rotates azimuth knob (44) until M1A1/M1A2 collimator (21) is sighted. 36 44