I left message and was contacted, the guy told me he inspected that barrel before it left shop, also I was told no pilot was used to cut crown and something about nylon plug which might left those marks, that's sound weird... I was told to go out and shoot it and if its bad send it back. I offered to show pictures what my barrel looks like, but he showed no interest in them...
I actually bought 2 barrels from them with different calibers, one 26" varmint another 30" bull contour, the varmint is great I couldn't find anything which would point to tool marks, but bull barrel has that weird stuff at the end of it. I inspected both chambers and they look great with nice finish, throats nicely done one both. Those marks at the end of the bull barrel are not very deep and probably will get worn out after I complete its break in, I hope ;-).
Saw the same thing in what I would bet is the same brand from the same and only source for them. It was a 300wm. Showed the same marks but only within about an inch from the crown. Didn't even see them before shooting. I doubt you'll see any issues. The barrel I used didn't. It was grouping about 1/2 MOA within 8 shots and didn't seem to foul badly. I'm sure it is mostly cosmetic so go shoot and enjoy.
got a chance to shoot it today, or break in. I did one shot clean, first shot was trapping copper right where scratches are, I did few passes with KG-2 and copper vanished quickly after 3rd shot clean with KG-2 scratches were no longer visible, after 5th shot I stopped doing break and fired 5 5-shot groups, the best group I got was 0.192 and worst 0.56", that's without any load development. I think I might tweak those loads to get tighter groups. I'll post picture of the muzzle after I remove carbon then after I clean it.