I full size my 308 brass base to datum .001 , also use the expander ball ,I don't neck turn my brass . To make it go smooth through the neck when lowering the ram , I lightly lube the inside of the necks with a Q Tip . Works well for me , runout is average .001 thats with nothing fancy , a Standard RCBS F/L die , tried the S Type bushing dies , didn't work for me , liked the idea of adjusting neck grip , again didn't work better for me. My chamber on my 308 is pretty tight , helps in brass life , a not a lot of stretching going on.