Chamber is OK... before being recalibrated they did not show these signs. before I used rcbs and did not give these signs..What do they look like coming out of the chamber? If they’ve been given the rings during firing from the shoulder of your chamber, the die tends to just touch the high spots, highlighting the feature. Could just as easily be the die shoulder too.
thank U ...The die is rough. It will smooth out with use. Don’t worry about it.
No..clean with wd40 and dried with air compressorDon’t worry about the marks. Did you clean the die with acetone to start?