The grenade launcher is a single-shot, shoulder-fired, breech-loaded weapon that fires a projectile using the
High-Low System. The main component is the frame that contains and integrates all of the weapon's mechanisms and assemblies. The weapon features a rifled barrel, which is hinged at the front and tilted upward ("break action") for loading and removing spent shell casings. The barrel in the "combat ready" position locks into the frame with a rotary latch, mounted at the rear of the frame. The grenade launcher does not have an extractor; instead notches were cut into the base of the barrel that enable the operator to remove spent shell casings manually. The HK69A1 has a
single action firing mechanism with an exposed hammer that is cocked manually with the thumb after loading a round. A manual safety secures against accidental firing; the safety is ambidextrous and provides a lever on each side of the frame, above the trigger (the lever in the "S" position – indicates the weapon is safe; "F" – ready to fire). The grenade launcher is aimed using
iron sights that consist of a front post (adjustable for elevation) and a rear sight that has a flip-up dual aperture for short-range engagements (50 and 100 m settings) and a folding ladder-type leaf sight for long distance firing (has notched steps for 150, 200, 250 and 350 m), that is folded down and over the barrel when stowed. The weapon has a synthetic
pistol grip, a lightweight telescopic metal stock with a rubber shoulder pad and sling swivels for use with a sling. The grenade launcher is typically carried in a thigh holster. ==Variants==