On the FCD, the crimp insert for revolvers will give you a roll crimp, for auto's, a tapper crimp. The inserts are interchangeable. So, if I am loading a 160 for my revolver, and it will not take a roll crimp, I use the insert for my 9mm. I also got rid of the knob that came with it and replaced it with a bolt and nut. This way I can lock the bolt in place and not worry about it moving. If you are going to be using different inserts, use 2 nuts and lock them together, so you can go back to the exact crimp you had before.