On no turn necks,you will have some differences in neck tention with a given neck bushing,or fixed neck die.However, you do want about .002 tention minimum,on your loaded rounds.Moving the bullet in and out with your fingers is too loose.Without presorting case neck thickness,I seat my bullets to a certain feel,and any that require less or more pressure to seat,I set aside to be ,either redone,or used for fouling shots,depending on the ammount that don't meet my datum pressure.