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 503 of 775

TM 9-2350-311-10

3-7 FIRE CONTROL ALINEMENT TESTS AND MEASUREMENTS

— CONTINUED

3-7.6

M117/M117A2 Panoramic Telescope Reliability Testing

a. Testing Reliability of Deflections

1

2

3

4

Install M117/M117A2 panoramic telescope (1) in M145/M145A1 telescope mount (2) (para 2–11.1).

Center the cross-level (3) and pitch level (4) bubbles of the M145/M145A1 telescope mount (2).

Set the gunner’s aid counter (5) to 0.

NOTE

• To prevent eye movement, a parallax shield can be made in two ways. One is to use a dust

cap with a pin hole in the center. The second way is to use a small opening marked off with

strips of tape.

• If reference point is less than 55 yards (50 m) away, you must use a parallax shield.

Sight on a reference point (6) at least 55 yards (50 m) away.

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