ANALYSIS AND NUMERICAL CALCULATION OF THE CAUSE OF ACCIDENTAL FAILURE OF A FIREARM WITHOUT EJECTION AT LOW TEMPERATURE

Failure of firearms without cashing significantly affects their performance and reliability. This study conducted an in-depth investigation of this key issue. In this study, a comprehensive analysis of the failure and ammunition structural parameters, such as the shell material, mechanical properties, surface treatment, and gun structural design parameters, including the barrel bore structure, roughness, unlocking stiffness, unlocking time, pre-ejection mechanism, and gas system structural parameters, was conducted. Through the use of theoretical formula for rigorous theoretical analysis, and with the help of Abaqus finite element numerical simulation software, the barrel and shell under the pressure of the chamber of the radial deformation of the accurate calculation, then carefully analyzed and compared with the actual measured value. The results show that many parameters of ammunition and firearms have a significant impact on the extraction process, and an unreasonable design of the chamber size, shell wall thickness, or machining error will lead to non-extraction failure. In addition, the actual shooting test revealed that the full combustion of porous powder in a low-temperature environment leads to an increase in the chamber pressure, plastic deformation of the shell case, and an increase in the resistance to the chamber, which leads to the occasional failure of non-ejection.