It has seemed in some of your writings, posts and videos that achieving very concentric ammo was the key to more accurate ammo, but maybe I misunderstood what you have been saying.
I agree that non concentric ammo is a symptom of something else being wrong with the process. It could be a bad sizing die, seating stems not matching the bullet, bad brass or bad loading technique. Inconsistent brass is the worst, which is why I try to buy as good of quality brass as is available for a cartridge, but sometimes I got stuck with using poor quality brass for a cartridge like a 7x57. Yes, Nosler makes brass for this cartridge but it is outrageous in price so I'm using Remington and Winchester brass, which is the worst brass I've ever measured. Variance of .003 in neck thickness and bullet runout of .005 -.010. I'm getting acceptable accuracy in my old Ruger M77 but it's been damn near impossible to get good accuracy in my brother's M70 FW. 140 partitions group into about 4", but I've been able to get 139 gr Hornady SP to 1-1/2 inch groups.
I will never be confused for a competition shooter, but I've been rolling my own ammo for over 35 years. I load for hunting rifles, not benchrest guns, but I try to use loading technique used by competition shooters. Many of these shooters are obsessed with preparing brass for consistent bullet release, and are not concerned with bullet runout. Consistent seating pressure is what they're trying to achieve.
Maybe it's another rabbit hole to go down, but that's what rifle looneys do.
