Question regarding Case neck and bullet run-out. What processes or techniques do you use beyond the simple chamfer and de-burr ? In my case, I have Norma brass, Hornady SST bullets, a Co-Ax Press and some Forster dies. In some situations I am getting .004 or worse and the very next case will be .001 or less. I’ve read where something as simple as rotating the brass 1/4 to 1/2 turn when sizing or seating works…. I’d really like to figure out where I am going wrong.

Does seating on or near the lands mitigate run-out ? Thoughts ?

I find the rotating 1/2 turn helps. Don't have the setup to measure it but accuracy is better IMO.

Measure your neck thickness on your case in 4 spots, every 90 degrees. Often times a case neck will be thicker/thinner on one side, causing run out.

Its in the brass as Chad suggested. Rotating will help on occasion but not a sure cure. Actually .004 is not horrible but I never like to get much over that for hunting ammo.

I am getting some pretty crazy differences too sometimes .03 off. Rotating the brass sounds like a good idea and I am going to try it. A buddy of mine told me to lightly lube the bullets before seating or lube in the inside of the necks, anyone try this?

I have never tried putting lube inside the neck before seating. By the time I am pouring powder and seating bullets those cases are clean and unless it's graphite, the thought of lube in the neck just doesn't make me feel comfortable. I have tried starting the bullet then backing off and completing the seating... not much difference in results.

The problem begins with the case neck being out of alignment and bullet seating makes a bad situation worse... I really hate to FL size the cases and then check each one but..... that is probably what I'll do for the January shoot.

I wouldn't "lube" the necks, per se. But you can try some mica to help. I have a nylon brush I would sprinkle some mica on or run the brush inside the mica and push the brush inside the case necks before seating. I only did this on some rounds that the necks were very thick or had a very tight bullet seat. If it's fired brass, it shouldn't be that difficult to seat if you cleaned the brass with corn cob or walnut. If you use Stainless steel, then it CAN make it more firm. It also depends on what cleaning solvent and additives are used in the solution. But I wouldn't lube the necks, as it can change up your seating consistencies, and maybe contaminate the powder.

Inside neck lube is accepted and recommended for bottleneck cartridges, not necessary for straight wall brass.