Installation Instructions for the M102 Howitzer

TM 9-6920-361-13&P

2. Sight through the breech boresight disc and

aline the horizontal boresight string of the gun with the

horizontal cross-hair string on the howitzer To raise the

barrel, tighten the front elevating adjusting screw and

loosen the rear elevating adjusting screw. To lower the

barrel. loosen the front screw and tighten the rear

screws.

3. When the horizontal crosshairs are in

alinement and the two elevating adjusting screws are

tight, tighten the four head cap socket screws.

Remove the howitzer boresight strings.

5. Select a distant aiming point (DAP) at least

1, 500 meters from the weapon. Sighting thru the breech

Step 1: Open the breech and place the adapter in the

boresight disc aline the 14.5-mm barrel on the DAP.

breech recess. The gib adjusting screws should be in

the unscrewed position. Make sure the adapter rests

6. Refer the panoramic sight to the distant

against the breech ring then turn the gib screws finger

aiming point. The reading should be zero. If it is not set

tight. Tighten the screws an additional 1/2 turn. Loosen

to zero, turn azimuth knob until azimuth scale reads zero,

lock screws before positioning adapter PN 11578967 in

then adjust the sight onto the distant aiming point using

breech recess. Tighten the screws to lock adapter in

the tangent adjusting screw.

breech ring.

Remove boresight disc and install bolt.

Step 2: Remove the four head cap socket screws and

the adapter cap.

Step 8: Turn the safety ring to the "tire" position. Place

the lanyard ring over the rear of the breech, matching

the openings of breech and the lanyard ring.

2-9.

Installation Instructions for the M102

Howitzer. The 14.5-mm gun barrel is mounted in the

breech of the M102 howitzer as a subcaliber device. To

mount the gun barrel, follow steps 1 through 8.

Step 3: Remove the elevating arc from the barrel by

removing

the

two

mounting

screws

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