Abstract: The matching of alterable caliber rifle is the key problem of the development of alterable caliber modularized rifle system. The numerical simulation models are established for 5.8 mm and 7.62 mm caliber rifles, and the numerical simulation models are verified by comparing the simulation results with the experimental results. The kinetic characteristic matching of bolt carrier, the ammunition feed matching and the ejection matching are analyzed based on the models. The matched-degree principle of the bolt carrier’s kinetic characteristic matching is built, and according to this principle, a reasonable design project is selected. The result shows that the kinetic characteristic matching of the bolt carrier can be achieved well by changing the diameter of the gas chamber; the stability of ammunition feed and the ammunition feed matching can be improved by changing the angle of ammunition feed slope and the rounding edges; and the change in the position of the ejection port is an efficient measure of ejection matching.

Key words: ordnance science and technology, modularized rifle, kinetic characteristic, dynamics simulation, automatic mechanism, ammunition feed, ejection