Avoid the carbide ring FCD. The one you want is the collet style FCD. However when you get it stock from Lee, the crimp band is too wide and it sits too high on the case mouth and actually crimps the boolit in front of the case mouth. WTH? Who needs the boolit crimped we are trying to size boolits to a specific size, not swage them down (which the carbide FCD does a very good job of), so the collet needs to be machined to narrow the crimp band to .050" or so, and drop it to just below the case mouth for it to work the best it can work. I do a good enough number of these mods, here is a thread showing how I improve the collet style FCD: http://castboolits.gunloads.com/show...=1#post2239315