In order to study the secondary engraving problem caused by the unequal rifling height between the revolver bushing and the barrel bushing of revolver automata, a finite element model reflecting the rifling height difference was established to analyze the secondary engraving process of the belt. Through numerical simulation, the stress, deformation and temperature were obtained when the belt was completely squeezed into the revolver bushing and the barrel bushing. The simulation results were in good agreement with the notch of the belt recovered in live firing, which indicated that the established finite element model had a certain credibility. The simulation results show that the unequal height of the bore liner and the barrel liner has a significant effect on the belt squeezing process. The half-height bore liner can make the belt squeeze into the bore liner more smoothly, but the belt will produce stronger impact when it squeezes into the barrel liner for the second time; Full-height rifling is more difficult when the belt is squeezed into the revolver liner, but it is smoother when the belt is squeezed into the barrel liner twice.