Just had a new gun built in 7 saum. Made some rounds last night and cycled them one by one. Each round was scratched as you see. I ran some brushes and patches a couple is times. Bolt closes easily and opens easily. Any ideas?
The vertical scuffs look to be from your die........ not sure what the horizontal scratches would be caused by, has something to do with cartridge rotation though.
Rough chamber could cause that. It could even just be dirty. Maybe clean the chamber itself, I'm assuming when you say you ran brushes and patches you were referring to the bore. Otherwise the chamber needs to be cleaned up. I'd suggest that you ensure that it doesn't get enlarged outside of saami specs
The horizantal scratches are likely from the case being held by the bolt during extraction and rotated against something in the chamber. Given that it appears to be in the same spot on each piece of brass, I'd inspect that portion of your chamber and you'll likley find your answer.