when the gun fires in rapid firing rate, serious factors such as the high ambient temperatures, thermal transients and corrosive-erosive environment existing at the bore surface limit the barrel life. Therefore, most of the current gun's rifling is produced by the radial forging process of the high-alloy steel. The residual stresses in the forged product directly affect the fatigue strength, stress corrosion, shape accuracy and service life of the barrel. In this paper, a FEA software DEFORM-2D based on the Updated Lagrange formulation with a rigid-plastic material behavior was used for modeling and simulating the residual stresses of the rifling part in the barrel. The material was modeled with the elastic-plastic behavior, and sliding-sticking friction model was utilized to modeling the die-workpiece and mandrel-workpiece contact. The quantitative effects of process parameters on residual stresses were investigated which would provide a useful tool for optimizing the process.