450 BM is the first and only straight walled rifle cartridge I have ever owned, shot and as a result the first straight walled rifle cartridge I have ever reloaded for AND first rifle cartridge I have ever crimped.
I set up and used my 450BM Lee FCD exactly as directed per the Lee instructions by screwing in the die till it made contact with the shell holder with the ram of my RCBS Rockchucker press in the 100% up position then added 1/2 turn more, tighten the lock ring and crimped a shell. Doing this required a force although not great I was a little surprised at the amount of force I had to apply to overcome resistance to complete the cam over action of my Rockchucker press. Again it wasn't what I consider an alarming amount of force needed but more force than I ever use for any other reloading step.
I have watched multiple videos on how the Lee FCD works and unless I am mistaken it crimps using a collet made up of four separate sections that uses the force of the shell being pushed into the die by the ram to constrict the sections of the collet onto the case just below the mouth to crimp the case around the bullet. Not much different than their excellent Lee collet resizing die I have been using for over two decades now.
I closely inspected every shell post-crimp and none showed any sign of any damage or actually any makings on the brass or bullet.
To be clear I am not saying that the Lee FCD in any way or form did any damage whatsoever to my reloaded shells or that the Lee FCD actually did anything wrong at all.
To be 100% honest if not for me having to overcome a noticeable amount of resistance to cam over my press to get the Lee FCD to function there is no other visual indicators the Lee FCD did anything or crimped the shell
I guess what I am asking is based on my results, am I actually using the Lee FCD correctly and is it actually crimping my reloaded shells.