Looking for consistency, the least tension to hold the bullet in all circumstances, provides the most consistency. Single firing, as in benchrest or at the range, tension provided by .001" difference was always my most accurate measure. Increase the tension and groups progressively got larger. Finding the happy medium for a hunting rifle where you might require a second or even third shoot, you had to have enough tension to hold bullets in cartridges in the magazine from setting back upon recoil. The most accurate off the bench was not necessarily the best for a hunt. I always used a difference of .002" for the benefit of accuracy, with the hope I wouldn't require a second shot. Take a note from the old benchresters. They used zero tension and allowed chambering to seat the bullet.
