Some dies sets let full reloading with 3 dies. Other folks may require a fourth die for that taper crimp. Taper crimping, in lieu of roll crimping, must normally be finished with the 9mm. My latest order to get a Lee 9mm carbide "undersize" resizing die that reduces the case https://9mm-dirty-once-fired-bras08417.blogscribble.com/36449935/9mm-reloading-options