Originally Posted by Buffalobob
If you have case neck runout then geometry says you will have bullet runout.
I've tried all sorts of bullet seaters including Wilson hand seating chamber types, a variety of floating collet dies for the press, even a Lyman Tong Tool with a die. All bullets tend to align with the case neck regardless of the type of tool.
Best solution is to use a full length sizing die without an expander ball and cases with neck wall thickness spread of less than .001". You can lap out the neck of a full length sizing die to 2 or 3 thousandths smaller than a loaded round's neck diameter, but it's easier to just get a bushing die from Redding or RCBS; both use the same bushings.
Bullet runout's best measured with the front V centered on the case shoulder slope. That's where rimless bottleneck cases center in the chamber when they're fired. Belted cases whose shoulder's set back a couple thousandths in a full length die do the same thing. Best part of this is any out of round of the case and/or chamber at the shoulder-body junction doesn't matter when full length sizing dies are used. Neck only sizing still allows some interference when fired case body diameters get too big. Resting the front part of the case in a V just behind the shoulder ends up with any out of round in the case at that point altering the bullet's real runout.
30 caliber rifles need no less than 2 to 3 thousandths runout. Bullet's straighten up very well and machine rest tests have proved this is enough. Any straighter's a waste of time. Especially if the loaded round's bullet just barely touches the lands when its chambered and pushed all the way forward by the firing pin like it is when its fired.