If you set up most FL sizing die by the factory instructions with the same brand shell holder you will be sizing to SAAMI headspace tolerance. With Redding if you read carefully, you are sizing to minimum SAAMI length. Which for most factory chambers is not needed. You want to set sizing die using fully formed LUBED brass. Using several cases that chamber with some extra bolt closing effort(bolt action). Than for hunting rounds you screw the die towards the shell holder in small increments(1/16 or less) of a turn of the die until the sized lube FREE brass chamber properly. I strip the bolt(bolt guns) to test brass to chamber fit. Hunting ammo, the stripped bolt must fall closed by itself, no additional effort.
AR's are different because chambering to set up sizing die can result in the brass shoulder moving(sizing down ) from the spring pressure of the action closing. The easy route to properly sizing AR brass is an ammo checking tool, like the Lyman ammo checkers. You can verify brass is sized to SAAMI spec and check finished ammo, so no surprise hard to chamber(forward assist needed to go into battery) and no mortor extraction to remove a stuck live round( not safe).