Abstract: In order to perform the feasibility study on the application of automatic mechanism for gas and floating barrel operated automatic action in high muzzle velocity grenade launcher(HMVGL) and reduce the recoil of weapon system, the structure parameters of gas operated device is adjusted, and the recoil energies of the barrel and bolt carrier assembly are matched. The basic equations of interior ballistic and flow problems which consider the effects of heat loss and floating barrel are derived based on aerodynamics and thermodynamics. The performance characteristics of automatic mechanism and the recoil-time curve are obtained by the calculation and simulation of launch dynamics of HMVGL. The reliability of the model is validated by comparing the simulation and experimental results. The pressure fluctuation of gas chamber is discussed with regard to gasport diameter, gas-port position and initial gas volume. The speed curves of automatic mechanism and the recoil curve are also analyzed. By means of automatic mechanism based on the gas and floating barrel operated automatic action, the maximum recoil of HMVGL can be limited within 1 100 N to achieve a low recoil launching.

Key words: ordnance science and technology, automatic weapon, gas-operated device, floating barrel, aerodynamics, modeling and simulation