1mile50

First of all, I believe you will have better luck asking your question on the Group Therapy board.

I'm assembling the components for a BR rifle, and it will have a tight necked chamber. Other than that, I can't give you a definative answer to your question, because the answer is only critically pertinant for someone shooting a tight necked chambered rifle, and at present I am not.

Still, the question begs to be asked, why are you using FL dies after going to the trouble of turning your necks? Using a FL die on brass with turned necks will shorten the case life. The thinner necked brass will not last as long as brass w/unturned necks.
Brass should be FL sized before neck turning, but not after. If you're lucky, the expander will size the neck id for a proper fit on the neck turner's mandrel. If it doesn't and you can't modify it on a lathe to do so, there is a caliber specific tool called an expandiron, that will. For the shooter with a standard necked chamber, the goal of neck turning is twofold. Remove the high or "thick" spots from the neck on the outside, and controlling neck tension. This is accomplished with a bushing neck sizer and annealing those necks. Given that everything else is done right, low velocity spreads will follow. You get no such benefit with a FL sizer. Other benefits of bushing neck sizing include lower T.I.R. induced by expander ball drag and longer case life, the less sizing involved, the less work hardening you get.

Your brass will of course tighten up after a few shots. Instead of a FL sizer, then you are better off with a "bump die", like this one from Redding. Body dies, or "bump" dies size only the body, not the neck. After putting all that labor into your cases, why screw them up in a FL die?