Aim\ To examine the floating performance and actual effect of hydraulic-spring floating machine. Methods\ The dynamic test on automatic mechanism and firing precision is accomplished for the floating machine gun and buffering machine gun in ball firing. Results\ The displacement

recoil-force and firing precision are attained in a running fire. Conclusion\ It can be verified to make machine gun float steadily by use of the designed hydraulic-spring floating machine and remarkably reduce the recoil-force and improve the firing precision.