C8, TM 9-2350-230-12
TABLE 11-6. SYNCHRONIZATION OF XM44/EI PERISCOPE BY OUTDOOR METHOD (Continued)
Step No.
Procedure
7
Pull and turn elevation knob counterclockwise to end of travel. Set slip scale to "1"
Pull and turn knob to "4".
8
Set both eccentric micrometers on the elevation link assembly to zero (fig. 11-43).
Adjust elevation link until boresight reticle is on same aiming point as the gun tube.
To adjust link, loosen two screws on connector and link and turn tube. Tighten both
screws.
9
If necessary, make a final elevation adjustment with the adjusting knob on periscope.
Reset the slip scale to "4".
10
Using the M1A1 gunner's quadrant placed on the breech block rail (A, fig. 2-28), ele-
vate gun to 89 mils (5 degrees).
11
Back vehicle up incline until bubble in gunner's quadrant is centered (approximately).
12
Observe target through boresight aid pin hole and re-lay gun on target aiming point by
laying low to high without over-travel.
13
With elevation boresight knob on periscope, align boresight mark of telescope reticle
on the same aiming point as the cross threads of the gun tube.
14
Read and record the deviation from the initial boresight reading (4) on the elevation
boresight knob scales.
15
Repeat steps 11 through 16 with gunner's quadrant settings of:
178 mils (10 degrees), 267 mils (15 degrees), 336 mils (19 degrees), and minus
124 mils (7 degrees depressed position).
16
Determine if deviations from initial readings exceed the maximum tolerance of 0.5
mil for synchronization at 0, 5, 10, 15 or 19 degrees elevation, and 7 degrees depres-
sion. If synchronization error exceeds 0.5 mil, return vehicle to position with the
maximum deviation and adjust periscope line of sight, by adjusting the eccentrics on
elevation link (fig. 11-43) so that one-half of error is removed.
NOTE. Inner and outer eccentrics must be -adjusted so that either red or white scales are aligned to
the same index on bo' scales, i.e., red scale to red scale or white scale to white scale. From
zero setting adjusting both eccentrics into red scales will lengthen the linkage and adjusting
both eccentrics into white scales will shorten the linkage.
17
Recheck boresight deviation at minus 124 mils to plus 336 mils (steps 14 and 15). Deviation
now should be within tolerance at each elevation. If not, recheck steps 2 through 17.
18
If periscope cannot be synchronized, replace periscope (fig. 11-41).
19
Remove boresight equipment (steps 2, 3, and 4).
20
Turn turret control and fire control switches off. Lamps will go out.
21
Turn XM44/E1 periscope control panel rheostat knob fully counterclockwise, position
dark filter in place (XM44E1 - filter to "OFF" position) and turn control panel peris-
cope switch to "OFF" position.
22
Close XM44/E1 periscope ballistic shield.
23
Turn vehicle MASTER SWITCH to "OFF" position.
11-34