It's not that complicated. Have a gunsmith verify the diameter of the neck in your chamber. Subtract from this .002" (neck clearance) and the bullet diameter. You now divide this by 2, gives you the wall thickness in the neck of your brass. Turn the neck of a few rounds to this thickness, might need to do it in more than one step. My finish cuts are around .0006". Polish the finished neck with 0000 steel wool. Seat a bullet in your preped brass, measure the neck diameter of a loaded round. If your using flat based benchrest bullets, make sure you measure over the pressure ring. If done right your loaded round will check .002" smaller than your chamber neck dimension. Neck clearance is a subjective thing, some use more, some less. It is felt that anything over .003" will have a negitive affect on accuracy.
