A mathematical model of interior ballistics for the amphibious rifle when firing underwater and validation by measurement

The paper is focused on study of the interior ballistics model of amphibious rifle when firing underwater based on the standard interior ballistics of automatic rifle using gas operated principle. The presented mathematical model is validated and experimentally verified for the 5.56 mm underwater projectile fired from the 5.56 mm amphibious rifle. The result of this research can be applied to design the underwater ammunition, underwater rifle and amphibious rifle.