A comprehensive simulation tool is developed to describe and optimize the cooling cycle in the melt-casting of Composition B. It comprises a multiphysics approach tackling heat, mass, and momentum transfers involved in the casting process. The highly nonlinear solidification step and development of thermal stresses are included. A V & V (Verification and Validation) approach was adopted whereby the model was verified against a benchmark problem and tested with a simple cylindrical geometry. Then, the approach was applied to a 105 mm caliber artillery shell and simulation results were in close agreement with experimental measurements. The model is equipped with a CZM function to account for adhesion between the solidified cast and the mold. During cooling, separation is possible and the size and location of gaps, depending on shrinkage and adhesion, are successfully emulated. The importance of controlled solidification is pointed out, especially regarding steep temperature gradients within the shell. (C) 2016 American Institute of Chemical Engineers AIChE J, 62: 3797-3811, 2016