Do you find you need to full-length size after the third firing? Just wondering how long one can get by with neck sizing only with less stretch in the AI case. 2 or 3 firings was about all I could neck size with 223 being chambered in an UL-UL. Gave up on neck sizing in general in that case.
I’ll neck size a few 3x cases and see if they chamber.
I was only neck sizing to make headspace on first firing, and then second firing because I knew some of the brass hadn’t fully blown out the shoulders completely by case capacity measurement.
Probably could get away with it for more firings I just hadn’t planned to