I come across this question a lot: Can you use an Expanding Collet in a True Length or Dead Length Style Collet chuck?
The answer to this question is a resounding NO!!
The reason being is that Rovi and other Manufacturers of Expanding Collets use a screw that is mounted in the front of the expanding collet.
This screw is pulled back by the machine’s drawtube. Being that the body of the Expanding Collet is held securely in the collet chuck, the only thing that moves is the expanding screw . When the screw angle engages the internal angle of the expanding collet, the collet opens up to hold the ID of the part. With this design, the Expanding Collet holds true linear dimensions. In essence, this makes a pullback style Expanding Collet into a True Length / Dead Length Collet. A True Length Style Collet Chuck works the opposite of a Pull Back Style Collet Chuck. When the Draw Tube Pushes forward, a sleeve pushes forward over the tapper of the collet (This would be for an OD Collet), thus clamping on the part. If you were to try to use an Expanding Collet in this type of chuck, it would no longer hold linear dimensions because the expanding screw would stay stationary. The entire Expanding Collet would be moving in and out of the collet chuck, making it have runout galore in addition to not holding linear dimensions.