Strange Case Markings?

[JTinTexas]

Are the marks on all the brass or just the 3 ?

The marks are on maybe 9 or 10 out of 50.

 

[JTinTexas]

My lesson learned is to improve my attention on inspecting the brass as I am shooting (even if I know they are light loads).

 

[Dusty Stevens]

You got a borescope to look in that chamber?

 

[ebb]

If it were just the three, I was thinking maybe you picked up someone else's brass, but not that many I wouldn't think. Ive never seen any marks like those ever.

 

[Chubbs]

Magazine lip ? Is it a new one. If not some contamination from cleaning routine got on to mag. Fully loaded more pressure to extract and load the round from the magazine. As mag emptys less pressure so no marks..

 

[ebb]

https://www.bing.com/videos/search?...55FCAB15329DB126230C55F&view=detail&FORM=VIRE Maybe its this?

 

[Coyotefurharvester]

Bolt lug grease that got cooked on.

 

[JTinTexas]

Rifle was being single fed, brass picked up off the table (vs ground) and I should probably buy a borescope and look in the chamber (Dusty thanks for that idea).

I may go shoot it this afternoon.