After my recent post about inconsistent runout, a friend and I figured out the reason for my excessive RO. The rounds that had a large RO were because I wasn’t lubing the shoulders enough when bumping. This was causing the shoulders/necks to be cocked even in a custom full length body & neck die. Because I was under lubing, this was giving me some rounds with a RO up to .008. Went back thru all my loaded rounds and my prepared brass and resized all. Also, the batch of loaded ammo that had excessive RO was all re-bumped using a bump die with 2X the amount of lube. The runout returned to .0005-.00015. Today, I shot at 500 yds shooting numerous 5 shots groups. Shooting the .008 RO rounds, most of the groups were approximately 20-30% larger. Going forward, if the RO of my loaded rounds are more than .002, they are going to be used as “foulers” only. Because of this process, all this brass is going to be re-annealed before using.
Bottom line, don’t skimp on the lube.
Ben
Bottom line, don’t skimp on the lube.
Ben