I am looking at buying a bushing based neck sizing die to resize the 308 cases from my bolt target gun. Right now, I am using a Lee Collet die which gets me about 3 to 4 thou of run out in a loaded round. I hope to get smaller run out numbers with a bushing die. I wondered if anyone had experience of the Redding type 'S', Forster Precision Plus or Hornady Match Grade dies to share ? Do they all bump the shoulder back a little when sizing the neck without sizing the rest of the case ? How much undersize do you order the bushings ? The literature says 2 to 3 thou, but it's clear that you can vary the case tension like this and not need to consider crimping.. Again, looking for input and opinion. Thanks..