Influence of the gas vent position on the initial movement of the bolt-carrier for the amphibious rifles when shooting under water

Abstract

This paper presents a mathematical model to study the effect of the gas vent position on the movement of the bolt-carrier for the amphibious rifles when shooting under water. This mathematical model was applied for the 5.56mm amphibious rifle for different gas vent positions. The result of this research indicates that under the impact of the initial water in the barrel bore and the gas cylinder, the bolt-carrier only moves when the distance between the position of the gas vent and the muzzle is not smaller 171mm.