I bought a bag of new, Winchester brass, for my new 22-250, last month. At the time, I noticed some of these had necks which looked to not be true to the cases' axis. I ran them through the FLS die and loaded them up. They are all now once-fired and resized. I'd hoped that the firing and resizing processes would straighten these necks up, but, it hasn't, at least on the ones with the problem. I loaded a group up, yesterday, and noticed excessive runout on some of these. As they are rotated, on the Forster gauge, you can see the neck is the problem.
So, I'm trying to think of ways to true the necks up on the next cycle. One idea is to run through the FLS die, check neck runout, and, if excessive, run it through again, preferably rotated 180. Second idea is to check neck runout on the fired brass, and run the off center ones through an expander die step before full length sizing.
Thoughts?