Abstract: A container necker has a necking die moved into contact with a container workpiece by a cam and a pilot urged toward the container by compressed air on a floating piston on which the pilot is mounted. The pilot is held in contact with the necking die by the air pressure acting on the floating piston and follows the necking die in unison into contact with the container. Compressed air flows through the pilot to inflate the container to increase its rigidity during necking. A radial surface on the pilot is engaged by the end of the container to stop the pilot while the necking die continues to the end of its travel to complete the necking function. In a second embodiment the necking die is fixedly positioned and the workpiece is axially moved relative to the die to effect the necking function.