As long as your not getting pressure signs, flattened primers, ejector marks, loose primer pocket and etc., with the round count you havein a .270, I would say you dont have a headspace problem!. Looking at your numbers, makes more than enough sense, Win and Rem brass is softer than Federal, but I beleive you are readding more into a problem than you really have!, your boltface is cut to accept a rim size of .473, the softer the brass, the more it will try to form that size under pressure. Though neck sizing will increase the life of your brass, I beleive you would be better off full length sizing for hunting purpose's do to the fact that it will feed easier for a quick follow up shot.