
What is interesting are these swipe marks across the ends of the case neck. Swipes are never across the complete ends of the neck but in distinct spots, sometimes one, sometimes two. All cases have this. Not visible in photo is the fact that the swiped area are bright signifying a recent event i.e. from the firing/extraction. I have tried cases with slightly longer neck i.e. 2.015" i.e. right up against SAAMI specs and I get the same thing i.e. never swipes across the whole neck end, just one or more small spot like this.
I am just curious as to what would cause this?