"Most probably its development was inspired by the Sino-Soviet border conflict of the late 1960s, as well as initial experience with several US automatic grenade launchers, learned from Vietnamese troops who were often on the receiving end of these weapons."
It being the Soviet AGS-17 automatic grenade launcher. An AUTOMATIC WEAPON firing a 30 mm grenade.
Those "several US automatic grenade launchers" including the fire team M79 weapon, firing a 40 mm round, there also being a hand-cranked version found on the Huey Cobra attack helicopter. That hand-cranked variety replaced by an automatic capable weapon subsequently.
The round as fired by the M79 deadly and gaining a lot of respect from the communist adversary in Vietnam. That grenade having a range far beyond the capacity of the hand-grown "pineapple" and not a whole lot less lethality that the mortar bomb as fired from a 60 mm mortar.
"First widely used in Vietnam, the M79 turned to be a complete success. Reliable and quite accurate in the hands of a trained operators, it provided extremely mobile firepower to smallest of the infantry units [one operator per five man fire team]."
The AGS-17 an obvious [?] Soviet response to American innovative and imaginative weapons design?
"The AGS-17 Plamya (Russian: Flame) is a Soviet-designed automatic grenade launcher currently in production in the Russian Federation and in service worldwide."
"The AGS-17 is a heavy infantry support weapon designed to operate from a tripod or it can be mounted on an installation or vehicle. The AGS-17 fires 30 mm grenades in either direct or indirect fire to provide suppressive and lethal fire support against soft skinned or fortification targets."
"Development of the AGS-17 . . . has been started USSR during in 1967"
"First prototypes of new weapon entered trials in 1969, and mass production commenced in 1971"
Indeed, it can even be speculated that the Soviets saw a drastic need for such a weapon, fire support at the company level THOSE TROOPS ON THEM BORDER WITH CHINA IN PARTICULAR REQUIRING ORGANIC FIREPOWER CAPABLE OF DEALING WITH MASSED FORMATIONS OF ATTACKING CHINESE INFANTRY, OVERWHELMING IN NUMBERS?
This image shows a Soviet Border Guard troop [KGB] equipped with what seems to be a prototype of the AGS-17. Guarding the border between the Soviet Union and China, 1969, the Ussuri river, during those repeated clashes between Soviet troops and the Chinese adversary. At least by 1969 the AGS-17 already in the Soviet arsenal and deployed?
Massed "human wave" attacks of the type used by the Chinese as encountered by the American forces in Korea having a counter and that being the automatic grenade launcher? Evidently the Soviet must have agreed with this appraisal?