Manual

SIG 556 Operators Manual 9 P/N 1511203 VER 12.7.2
firearm in normal use. Without ear protection, repeated exposure
to shooting noise may lead to cumulative, permanent hearing loss.
2.0. Mechanical Characteristics And Weapon Theory
2.1. Weapon Description
2.1.1. General
The SIG 556 Rifle is a semi-automatic, gas operated weapon,
with a rotary bolt mechanism. Semi-automatic means one round
will fire each time the trigger is pulled until the magazine is emp-
tied of ammunition. The rifle is chambered in 5.56mm NATO
and is compatible with .223 Remington ammunition.
2.1.2. Barrel With Receiver And Gas System
The barrel is mechanically mated to the receiver. The flash sup-
pressor is screwed onto the muzzle end of the barrel which fea-
tures a ½ x 28 TPI thread pattern. The gas block, which is fixed
on the barrel, contains the gas port, locates the gas system (gas
tube and operating rod), accepts an optional front sight and also
serves as support for the hand guards. The receiver guides the bolt
and bolt carrier and houses the locking system. An accessory
mounting rail is fixed to the upper part of the receiver, providing
an attachment point for sighting systems and other accessories.
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