I think you may have missed a part of my process which was detailed in an earlier post. Initially, after receiving them as once-fired brass, All cases were decapped with a Lyman Universal decapping die, cleaned, then annealed BEFORE sizing, sized, cleaned again to remove lube, then final trimming, beveling and then final cleaning, then the primer added.
Repeat, every case was annealed after primers were removed using a Lyman universal, then washed, then annealed BEFORE sizing or trimming the first time I used them. There was no expanded neck spring back on the sizing after my initial reload and firing. That is why I did not continue to anneal each time. That doesn't mean I won't have to after a couple more firings. I will monitor. These have been a lot easier than the 5.45X39 Russian from Remington 222 cases. I appreciate the help I try to learn something new every day. I haven't been on this forum long, but I have been reloading for over 50 years. I have an RCBS Jr, a RCBS turret press with 17 full turret plates (2 cals per turret) and a Dillon 750XL with 12 caliber sets. Using a mill and lathe, I've built 9 80% AR-15s, all different calibers, including AR-9, AR-45, 458 SOCOM, 50 Beowulf, 6mm ARC, Grendel, 5 80% AR-10s with different callibers, including 6.5 Creedmoor, and restored (welding included) Remington Rolling Block, UZI, PPS-43, Sten, 4 AK-47 models, 1 AK-74, and am currently welding up a CETME. I also reload Mauser, Arisaka, Mosin Nagant, Carcano, etc., so I've been around the block a couple of times, but the 8.6 is new to me, (because of lack of published data) not so much for super, but for subs. Those I have never done before, and this one with a very fast twist. The reason I listed so many items is, time permitting, if anyone needs help on something I have done, I'm here. If I don't know the answer, I will say so.