Machining marks on fired case shoulder

[PLhunter]

I recently had a local gunsmith profile and chamber a k&p barrel. I have about 100 rounds down the barrel at this point. Cleaning cases I noted texture and rings around the shoulder. I was also cleaning cases from my old tikka chamber and they were perfectly smooth.

First does anyone think this is an issue worth bringing back to the gunsmith? The gun shoots great. BUT I’ve already cleaned the chamber twice because I’ve had pressure emerge on loads that started fine.. I realize this could be barrel break in too. The pictures
don’t really do it justice. I have some chambers with faint rings but these are actually palpable.

 

[wapitibob]

Dull reamer. My stw is a lot worse than that and it shoots fine.

 

[Lawnboi]

Zero issue.
Here’s an extreme example. This is 7 times fired brass that came from my most accurate 6 creed barrel I ever owned.

 

[PLhunter]

Zero issue.
Here’s an extreme example. This is 7 times fired brass that came from my most accurate 6 creed barrel I ever owned.
View attachment 1042883

Dang!!! Do you have any inconsistent pressure issues? My accuracy is great. Just wondering why I have inconsistent pressure.

 

[Lawnboi]

Dang!!! Do you have any inconsistent pressure issues? My accuracy is great. Just wondering why I have inconsistent pressure.

None. I doubt it’s from the machining.

 

[wind gypsy]

I've got a new barrel that is leaving similar marks on cases that is more notable than I've seen in the past.. I figured it should be fine as long as the body/neck/throat machining is good and it seems to be.

When you look at a chamber in a bore scope, the shoulder is usually the area with the least smooth machining.