In order to solve the problem of selection and control of key process parameters in ammunition press-fitting technology, the factors that affect the quality of pellet press-forming are studied. Taking the PBX explosive as an example, a combination of test and simulation, combined with the characteristics of the explosive, simplified the PBX explosive powder into a limited number of HMX spherical particles coated with a binder, and established a 3-dimensional mesoscopic model of the explosive system. The finite element simulation is used to simulate the pressure pressing process, and the rule that the pressure and pressure holding time have an effect on the quality of the pillar is obtained. The results show that the research can provide a reference for the development and production of ammunition charges and has certain practical value.