Mr. Wynne good write up on brass prep and as Al stated the key is consistency. What ever was done during the initial tuning process DON’T CHANGE IT. There is no secret neck dimension, prep process, or secret dipping compound to make a rifle out of tune shoot. How many times have you heard someone say they went to XX primers and the rifle really started to shoot. Fact is the rifle was never in tune and by changing to XX they lucked out and brought it in to tune. While back we took Wynnes load’s and left the necks carboned like I do, load went to crap with changing only this simple step. It works for me because I tuned this way at the start and his were cleaned when his load was tuned. Consistent neck prep is critical and one of the easiest way’s to screw things up
Not about necks but about tuning I had to change powder lot’s today. H4350 same load that has been a tack driver (597 at the bottom) new powder is 75fps faster and 15 shot groups went from .75″ at 300 to 2″. After consulting my best friend Quickload it was determined .8 grains less powder to get back in tune where we were.
My Mistake. When you get a rifle tuned and shooting buy enough primers, powder, and bullet’s of the same LOT number you tuned it with to shoot out the barrel and some extra.