I'm doing some loading for a friends .270 win he bought new RCBS dies and I FL sized all the new winchester cases he bought before loading. I cleaned / polished once fired brass and sized. On a whim I ran some thru my RCBS Casemaster to check neck run out. On about 90% of the fired / sized cases the neck run out was .004". I checked to new but sized brass and most of it was .002" or less run out with maybe 25% .004" or more. So then I took 3 cases that had been fired in his rifle, cleaned them measured neck run out before sizing, less then .002" most @ .001" took out expander / decapping stem and ran them thru sizer die, all were at .004" run out. So my question is , what is acceptable neck run out on hunting ammo and should I have him return these dies for new ones. Or is then some other way of checking to see if its the dies or something I'm doing that is causing this. I did clean the sizer die good today to make sure nothing was in there, i.e. lube build up. Any thoughts.