Heckler&Koch MR762A1 User Manual

Page 19

Fig. 63 – Installing the bolt assembly into the upper receiver

h. Push the charging handle and bolt group completely into the upper receiver until the

locking lugs on the bolt head engage the locking on the barrel extension and the latch

on the charging handle engages the oval locking surfaces on either the left or right

hand sides of the upper receiver (Fig. 64).

Fig. 64 – Completing installation of the bolt assembly into the upper receiver

4. Upper and Lower Receivers:

WARNING: Always use the Disassembly Tool to disengage the detents on both the

rear takedown pin and the front pivot pin. Attempting to install the pins without

disengaging the detents could lead to damage of the lower receiver.

a. Ensure that both the captive front pivot pin and rear takedown pin are drifted out to

the right hand side of the receiver. If necessary, use the small surface of the MR762A1

disassembly tool.

b. Place the upper receiver pointed downwards with the flash hider resting on a padded

surface.

c. Mount the lower receiver to the upper receiver. Drift the front pivot pin from right to

left. The pivot pin will not completely lock but it will engage the upper receiver (Fig.

65).

d. Insert the small tip of the disassembly tool into the spring loaded detent located in

the center of the rear pivot pin. While pushing on the disassembly tool, drift the pivot

pin from right to left until the pivot pin reaches its limit of lateral travel. The tip of the

pivot pin should be visible on the left hand side of the lower receiver (Fig. 66).

Fig. 65 – Closing Upper and Lower Receiver

e. Insert the small tip of the disassembly tool into the spring loaded detent located in the

center of the rear takedown pin. While pushing on the disassembly tool, drift the rear

takedown pin from right to left until the rear takedown pin reaches its limit of lateral

travel. The tip of the rear takedown pin should be visible on the left hand side of the

lower receiver.

Fig. 66 – Detail of the rear Takedown Pin showing spring loaded detent.

f. Install the disassembly tool into the storage channel located at the back of the

buttstock.

g. Mount the recoil pad onto the back of the buttstock with the recoil pad perpendicular

to the buttstock. Ensure that the recoil pad is flush with the buttstock and rotate the

recoil pad clockwise one quarter turn until the recoil pad engages the locking surfaces

located on both the top and bottom of the buttstock.