The FCD is unnecessary if you do all the steps right. I use a Redding taper crimp die because I do not want my bullet diameter affected.Well, that's just it, isn't? That is what the FCD is all about in theory, but too many times it appears indispensable.
If I eliminated an FCD operation, I certainly would still want to own an FCD and have it standing by as needed. Problem is, now I have to gauge every round because I didn't cover variations with an FCD operation. I don't want to find out later that the ammo is not reliable.
Why should I be forced to use someone else's commercial ammo just to gain confidence that it is reliable enough for a match? Why is my ammo only considered good enough for range practice just because I am too stubborn to use an FCD? The part I don't appreciate is having to own a certain type of press just to fit in that extra operation. Oh well.
I plan to carefully go through the process laid out in noylj's post. I will try one more time to see if I can get consistent OAL without a case collapsing. I will also check the .472 finished diameter at the case mouth that bds stressed a number of times. I have a lot more skill and insight now than when I first tried to set up dies. That's always the way. Here I am using an FCD and nothing is broken, and I am trying to fix something. Actually, being able to drop an operation would be very useful in a couple of my scenarios, primarily when limited to three stations and doing all operations on the press (priming).
The problem with seating and crimping at the same time is that this simultaneous operation depends on a consistent case length. Otherwise, short cases won't get crimped enough and long cases will dig into the bullet before it is fully seated- these are the problem rounds:
The case mouth crapes the bullet shank and holds the lead shavings in a place where they interfere with chambering. In addition, depending on lead hardness, the case mouth stops digging into the bullet shank and the case wall starts to peel away from the bullet just below the crimp.
Some people are talented enough to peel the whole case away from the bullet and can spin the bullet (which is held in place only by the crimp) inside the case with their fingers. They go on various internet sites asking if they need more crimp.