The HK69A1 is a 40 mm grenade launcher developed and produced by the German arms manufacturer Heckler & Koch (H&K). The weapon was designed to engage enemy troops and strongpoints out to a distance of 350 m; it can also be used to deploy smoke grenades and illumination flares. Development The launcher’s history dates back to the late 1960s, when development began of a weapon intended to be fitted (using a special mount) under the barrel of the 7.62×51mm NATO G3A3 rifle. In 1972 the prototype was unveiled of what would ultimately become the Granatpistole HK69. After being evaluated, the decision was made to develop an autonomous stand-alone version of the grenade launcher, which was created in 1979 and designated the HK69A1. In the 1980s the weapon was adopted into service with the German Army as the Granatpistole 40 mm (known also in the abbreviated form GraPi). It is also used by the special forces and security personnel of several other countries. Design details 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