.... continued...
Upon closer inspection (cheap jewlers loupe), the mark wasn't actually a radial shaped swipe mark but a line matching the profile of the extractor in the bolt face. Its always opposite the round ejector mark.
This is what I see in your case headstamps: the circle is the round ejector mark, the red line is the crease from the extractor trying to pull back on the rim before the case springs back from combustion (sealing the chamber). The telltale sign is the crease is always opposite the round ejector mark where a "swipe" would be randomly located. I suspect your slightly overgassed.
I edited your photo to show you what I see:
[ATTACH=CONFIG]20129[/ATTACH]
Upon closer inspection (cheap jewlers loupe), the mark wasn't actually a radial shaped swipe mark but a line matching the profile of the extractor in the bolt face. Its always opposite the round ejector mark.
This is what I see in your case headstamps: the circle is the round ejector mark, the red line is the crease from the extractor trying to pull back on the rim before the case springs back from combustion (sealing the chamber). The telltale sign is the crease is always opposite the round ejector mark where a "swipe" would be randomly located. I suspect your slightly overgassed.
I edited your photo to show you what I see:
[ATTACH=CONFIG]20129[/ATTACH]