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There is no need to set a shoulder back further than it's fired location when resizing, it's already shrunk back at least a thou anyway.
The headspace tolerance on most bottle neck cases is about 6 thou. A die moves almost 72 thou per turn (14 turns per inch) so a quarter turn moves the die about .180"; that's a massive change! A change of 1/8th turn moves the die some 9 thou, about 50% more than the full tolerance range. Meaning stick to 1/16th turns if you want to get it right without by passing the mark.
Adjusting a sizer 'right' demands a gage that reads shoulder locations in thousanths. That means either the Hornady or Sinclair cartridge head space tools on a caliper OR the RCBS Precision Case Mic (toss the dummy cartridge seating gage device) OR the Innovative Technologies dial indicator tool.
Neck sizing is vastly over-rated for accuracy and case life in factory rifles. Most will shot as well or better when the cases are FL sized and there's little or no difference in case life.
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