 The Chinese military began research into grenade launchers during the 1980s.They started off by examining American weapons captured in the Vietnam War including the 40×46mm single-shot M79 and M203; they were also familiar with the hand-cranked Mk 18, as well as the 40×53mm XM75 and Mk 19.China also obtained samples of the Soviet 30×29mm AGS-17 captured by the Mujahideen during the Soviet–Afghan War.