Converting Starline 6.5 Grendel brass to 6mm ARC

[BehindEnemyLines]

So I went ahead and resized 50 pieces of 6.5 Grendel brass to 6mm ARC yesterday and noticed today some marks along the top of the neck and one around the center of the brass this morning.  I think the 2 lines at the top of the neck are what are referred to as "vampire marks" from the feed ramps?

   

I'm not sure what may be causing the ring around the center of the brass.

   

I tried rubbing the ring around the center of the brass but it doesn't seem to have had any affect.

The last thing I did yesterday was to chamber them and closed the bolt to make sure they would fit.  I think this is where the marks occurred but cannot say for sure.  Any ideas?  Should I be concerned with either of these marks?

[Lemonaid]

Pretty normal except for the ring. Could be from when the barrel was chambered. From what I can see in the pics it looks minor and unless it bugs you a lot most likely won't be a problem. Check the chamber with a bore scope (a $50.00 tool) an if there is a ring there a quick chamber polish at that location in the chamber would likely get rid of it.
On the plus side, I was looking for a way to mark my brass so I could tell at a glance if was 6.5 Grendel, converted 6mm PPC, or converted 6mm ARC. Having a ring on the ARC would work.

[BehindEnemyLines]

Thanks Lemonaid. I took a bore scope to the chamber and didn't see anything real obvious. If there is something there it's probably not obvious as the ring in the center of the case is not real deep. I'm just going to roll with it as is until I get a chance to run some rounds through it. I also bore scoped my sizing die and did not see anything significant there either and cleaned it just to rule it out. If I do figure what is causing the ring I will be sure to let you know so that you can mark your 6mm ARC that were converted from other brass as well

[trianglevelvet]

   
Did you use one of these to deburr after trimming?

[BehindEnemyLines]

Yes, I did. Grabbed it instead of pulling out the Lyman Case Prep Center and setting it up.