Sorry this reply is so late I haven't been on the forum in a while.
I have Redding FL dies. I use .270 Win brass only. It provides the longest neck when formed.
My brass prep consists of running a flash hole deburring tool in every case, sizing in redding FL sizer die. This will leave a "bump" on the neck. Check by chambering for a "crush fit" if it is too loose then back out the sizing dies until you need a slight amount of force to chamber. Critical because the "bump" assists in correct headspace by creating a false shoulder.
My rifle is chambered so that I need to turn the case necks. I turn mine from the mouth to the start of the "bump". Turn the necks to .013" (my chamber only).
Load up some fireform loads. Try them out.
feel free to email me for more info on fireforming or anything else you need.