In order to improve the charge quality of ammunition, it is proposed that taking water bath as environmental medium to control ammunition charge solidification. The author analyzes the factors that affect thermal transmission efficiency in the solidification process of charge, use simulation and technical process test to analyze and verify the feasibility of this technology, and use the melt-casting explosive with low viscosity and the simulated ammunition with irregular melt-charging mouth to verify application effect. The verification results indicate that: water bath curing can control ammunition charge to be solidified from bottom to top, and improve charge density, solidification speed, uniformity and quality. It can also improve the particle settlement situation in the melt-charging process of ammunition and improve the ammunition’s destructive performance and using safety.