TAILIEUCHUNG - On the interior ballistics of an underwater personal gun

This paper deals with solving the problem of interior ballistics for a concrete personal underwater gun. The governing equations of the problem are carefully discussed because the water resistance force acting on the bullet is quite different from that of the air. These equations are used to create software for analyzing and designing an underwater gun. The calculated results are in very good agreement with the experimental data. | Vietnam Journal of Mechanics, VAST, Vol. 38, No. 3 (2016), pp. 215 – 222 DOI: ON THE INTERIOR BALLISTICS OF AN UNDERWATER PERSONAL GUN Nguyen Sy Hoa1 , Tran Van Tran2,∗ , Tran Thu Ha3 1 Le Quy Don Technical University, Hanoi, Vietnam 2 VNU University of Science, Hanoi, Vietnam 3 Institute of Mechanics, VAST, Hanoi, Vietnam ∗ E-mail: trantv@ Received December 02, 2015 Abstract. This paper deals with solving the problem of interior ballistics for a concrete personal underwater gun. The governing equations of the problem are carefully discussed because the water resistance force acting on the bullet is quite different from that of the air. These equations are used to create software for analyzing and designing an underwater gun. The calculated results are in very good agreement with the experimental data. Keywords: Interior ballistics, underwater, gun, muzzle velocity, propellant charge. 1. INTRODUCTION In practice every gun has been created for some early chosen operational aim in some specific fighting conditions. All these factors lead to the designing the geometrical form of the gun and its bullet that might make the gun more efficient in use for reaching the chosen aim. When the geometrical sizes and weight of the gun and the bullet are defined the interior ballistics should work out a propellant charge that will give the bullet the desired muzzle velocity without any damage to the weapon. The theory of ballistics including both the interior and exterior ballistics had started long ago. Before the end of the World War II the theory was mainly developed for guns of different caliber. Next the ballistic theory has been expanded for rockets. Fundamentals of the theory of ballistics can be found in numerous books such as [1–4]. Ballistic calculations for underwater weapon are not as popular as for guns used on the ground. The main difficulty of underwater ballistic calculations relates to the high density of the environment.

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• On the interior ballistics
• An underwater personal gun
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