What are the cons to having too much or too little neck tension on a 308 round for a Bolt rifle? I measured some rounds a few weeks ago and got a neck reading of .336 +/- .5 So I bought a bushing size of .334 I just remeasured some more rounds, same brass (winchester) and Im getting a reading of .337.. Will having neck tension of .003 or .004 make a difference when shooting?