The biggest problem I had when I started reloading was the meaning of the work "crimp".
To me, the "common-sense" meaning of the word crimp is that it is tighter than the rest of the case and holds the bullet in place, such as you see on a .357 or .44 bullet, what I now know to be called a roll crimp.
On 9mm, .40, .45, etc., we use the word crimp but it doesn't have the same meaning. On those rounds, the case is sized slightly small and the tension of the case around the bullet holds the bullet in place. The crimp is only intended to make the case wall perfectly straight, removing the belling you put in with you expander die, so that it will feed properly.
If you try to "crimp" one of those rounds, you will actually just end up resizing your bullet, making it loose in the case, and having the actual opposite effect of what you want.
As has been suggested, mike a factory round and see what the diameter is at the rim of the case and try going for that.
I have quit using the Lee FCD for 9mm, .40 and .45, my Hornady dies do a fine job with the taper crimp die as the last step and my press is a whole lot smoother to operate. I alway had quite a bit of drag from the FCD. The only real good reason to use the FCD that I see is as a final gauge to make sure the round will chamber in your gun, but I've never had a problem with that with my regular dies.
They work great on bullets with cannelures, I love it on my .223 rounds.