Marks on brass - looking for some insight

[Zak2006]

Shot 60 rounds and all had the little mark on the neck as shown in the picture. Anyone have any insight as to what may be causing this? Should I be concerned? Brass looked great otherwise with this mark being the only possible area of concern.

I do not reload. Gas was tuned for 3 o’clock ejection with lock back on last round. Those are cases from 150gr Federal Non-Typical Whitetail I was using to get on paper and get the gas right.

Aero receivers
20” Rainier Ultra Match Mod 2 in 308
Lantac NIB enhanced bcg
JP SCS with stock spring
10 round pmags
I can provide more build info if needed.

 

[Jakeweb09]

I don’t think it’s your chamber as it would be more of a long scrape vs a small indent, could be hitting something on the way out.

 

[FCS]

Neck of case is hitting on barrel extension, lug raceways.
Normal ding.

 

[Strangedays]

Neck of case is hitting on barrel extension, lug raceways.
Normal ding.

That’s what I was thinking also.

 

[flyright]

Perfect. Now you can toss that in with other brass when you tumble and still be able to ID which gun it came from when you're done.

 

[Zak2006]

Thank you all!

 

[Steel head]

Neck of case is hitting on barrel extension, lug raceways.
Normal ding.

This.