autogun said:

China developed a shoulder-fired launcher to take the NATO 40mm HV rounds (see my web article on grenades). Unless I've missed something, the current western projects are for Rheinmetall's MV loadings.

True, but that has some extensive recoil mitigation.  The China Lake/Airtronic design is literally a pump-action shotgun scaled to 40mm.  With no recoil system, the HV round in particular would be punishing.  MV rounds are manageable (barely), hence my suspicion that the Airtronic mod was to take MV, not HV rounds.

taschoene said:

MV rounds are manageable (barely), hence my suspicion that the Airtronic mod was to take MV, not HV rounds.

I agree.