TM-9-2350-311-10

HOWITZER, MEDIUM, SELF-PROPELLED, 155MM; M109A2, M109A3, M109A4 AND M109A5

TECHNICAL MANUAL; OPERATOR’S MANUAL

NOVEMBER 1994

TM-9-2350-311-10 - Page 497 of 775

TM 9-2350-311-10

3-7 FIRE CONTROL ALINEMENT TESTS AND MEASUREMENTS —

CONTINUED

3-7.4

Boresighting the Weapon

Boresight using the test target method (para 2–12.2).

3-7.5

Leveling the Cannon Tube

a. Leveling the Cannon Tube Using the Cannon Tube Leveling Fixture (if Required)

NOTE

• Use of cannon tube leveling fixture is required if cannon tube does not have quadrant seats

on muzzle brake end of cannon tube.

• Recheck gun trunnions. They must be perfectly level for this test.

1 Set zero on the M15 elevation quadrant (1). Elevate or depress the cannon tube (2) until the elevation

bubble (3) centers.

3-93