Manual

SIG 556 Operators Manual 43 P/N 1511203 VER 12.7.2
b. Push the operating rod in until fully seated. The
operating rod should move freely through the gas tube.
4. Install the gas valve:
a. Ensure the stop pin recesses on the back of the gas
valve tab face the barrel.
b. Insert the gas valve into the gas tube (the gas valve will
seat over the operating rod).
c. Depress the stop pin and rotate the gas valve to the right
to Position 1.
d. Release the stop pin. Check to ensure the gas valve
indexes in Positions 1 and 2.
5. Install the upper hand guard:
a. Insert the front into the gas block.
b. Push the rear downward until seated.
6. Install the lower hand guard:
a. Press the hand guard upward against the upper hand
guard, ensuring the locking tabs are aligned with each
other.
b. Press the lower hand guard forward until the front is
secured by the gas block and the pivot pin notch is
aligned.
7. Assemble the bolt head and bolt carrier:
a. Place the bolt carrier in your hand, upside down, cam to
SIG556 OM 12.06.qxp 1/8/2007 2:26 PM Page 43