Gunsmithing Question about marks on shoulder/neck and bore shoulder

[Mumbles76]

I have myself an AR-10 in 6.5creed (not suppressed). This batch is factory 120g Hornary ELDM.

No real issues to speak of, but i was looking at my brass today and noticed a few things...

1. Using the borescope, i noticed a rather sharp gouge on the shoulder of the chamber. See screenshots.
2. All my brass has this mark on the neck and uneven burn around the neck.

Is this anything to be concerned about? This is my first big rifle - so i don't have any body of knowledge on what it should look like. And i was going through the mechanics in my head and thinking, what is making that dent in the neck of the casing and i came up short.

Any advice would be greatly appreciated.

Video link showing my casings:

 

[Holliday]

I don’t see how the mark in your chamber is related. Did this brass hit the ground?

 

[Mumbles76]

Did this brass hit the ground?

it did.

 

[Mumbles76]

The concern here being that i won't get proper seal. And i'm wondering if the uneven burn marks on the neck are a result of this gouge.