Abstract: A method for extruding a metal tube to a precise internal diameter and a precise linear camber is provided by sizing and straightening the tube with a mandrel after the tube has been extruded to an approximate size. The mandrel is to have a taper so that a smaller end is inserted into the tube and then the mandrel is advanced to cause the tube to be inelastically deformed. The insertion is to proceed at a relatively slow speed in the range of 2.2 feet per minute to 1 inch per second until a desired constant diameter portion of the mandrel has been fully inserted into the tube. The insertion speed thereafter can be increased up to a speed of 48 feet per minute through the remaining length of the mandrel. Withdrawal of the mandrel preferably also occurs at a first slow speed until the constant diameter portion is withdrawn from the tube and then further withdrawal can proceed at a higher speed.