I was full length sizing some brass I fired in my new AR15. I noticed that it did not take all that much force to get the job done. I took a FL sized case and compared it to an un-sized case and noted that it was just bumping the shoulder, but more than anything it was resizing the neck. I took a un-sized case and chambered it in my AR and noticed no difficulty in doing so.
Can I just neck size my cases until they don’t chamber? I know everything I have read says not to but I am one of those guys that wants to know “why” all the time.
Forgive me if I posted this is the wrong subforum.