US Patent 7478550 Shell press and method for forming a shell

The invention generally relates to an apparatus for forming a shell. The apparatus has a die center and a panel punch located in opposed relation to the die center. A panel punch piston is coupled to the panel punch. The panel punch piston has an upper end and a spacer member is disposed concentrically around an outside surface of the panel punch piston at or proximate to the upper end of the panel punch piston. The upper end of the spacer member is in contact with a lower end of the panel punch and the spacer member is located proximate to a peripheral surface of the lower end of the panel punch. A method for manufacturing a shell is additionally provided as well.