In order to extend the coverage area on fire range of anti-riot launcher and improve the efficiency of treating group events

the influence factors of fire range and muzzle velocity of projectile of the domestic nine-tube 38 mm anti-riot grenade launcher were analyzed theoretically.And the relationship between charge density

barrel length and muzzle velocity of projectile were analyzed quantitatively and selectively.A technical way of increasing charge density and barrel length was given to raise the muzzle velocity of projectile.The balance design of the emitter was carried out by the parameterized entity model-building software Pro/Engineer after increasing the barrel length.The effect on the buffer hamulus' strength was analyzed by the finite element analysis software ANSYS after increasing muzzle velocity of projectile to 75 m/s

and its strength was still meet the design requirement.The research illustrates that both charge density increase and barrel length increase can improve muzzle velocity of projectile of the anti-riot launcher for its extended-range and optimization design.