A method is described for making a retort container having one or two metal ends. A heat-sealable material is present on one or both of the container side wall and the/each metal end. The/each metal end is seamed onto the container body, and the resulting container assembly is conveyed on a conveyor adjacent to an induction sealing head and then adjacent to a cooling device. A pressure belt engages the upper end of the container assembly to keep the metal end from coming off the container body during the induction heating and cooling processes.