I am shooting norma brass out of my .300 win mag and using Redding Bushing neck sizer die. I was going to use the mic and sort the brass into lots depending on the neck thickness. I started doing this and I figured out really quickly that it wasnt going to work due to the variances of the neck thickness on each piece of brass. I will check 3 places around a neck and get readings from .0140 to .0148 or so and the next one will be .0146 to .0153. I am not concerned with these numbers exept I dont know what bushing to use. I could take an average of .0145" X 2 = .029. .029 + .308 = .337. So .002" neck tension would be a .335" bushing however on the low end of thickness .0140" this would only be .001" neck tension which is not good for a magazine fed rifle. So I could go .334" bushing for the safe side then on the high end of lets just say .015" that would be .004" neck tension which is getting pretty high. Like I said I was going to sort them into different lots but they are all about the same but just depending on where on the neck you measure I get a different thickness. I know neck turning would alleviate this whole problem but i have been there so many times and everytime I just end up ruining good brass and get a headache and loose sleep over all the brass I ruined. So other than neck turning, what are my options?