Facet mounted system by having an integrated MILSTD 1913 rail piece for sighting techniques. Suitable for use Using the M203. This is called carrier tilt. The ALP permits the operating rod to wiggle to correct to the downward force within the bolt and transfers the force straight backwards in line https://knights-armament-quad-rai97396.designertoblog.com/60980835/little-known-facts-about-knights-armament-m4-quad-rail