Specifically I am loading Grendel rounds. I am going to order the Redding Type S FL sizer and needing a shove in the right direction. Reading the Redding website, they state that a bushing selection of .001" - .002" less than the neck OD of a loaded round is recommended. Then other sources state .002" - .003". So my question is what is the proper neck tension for an AR-platorm gas gun with focus on the 6.5mm Grendel (if that matters). Thanks!