Cut Marks on Neck

[Shaikh]

Hello
Experts advice needed just load my 243 once fired brass after firing no pressure signs no Hot load fired 20Rounds evrey Brass has Cut marks on Neck Help required pics attached

 

[Dmagna]

Have you already resized the once fired? Or are these right out of the chamber? Trying to eliminate the die from the issue, if it your chamber have you noticed it before?

 

[243winxb]

Clean both, die and chamber.

 

[LoneTraveler]

I would check the chamber first. From the scar on the case it looks like there is a burr at the neck, shoulder junction. When the case is fired and it conforms to the chamber, The brass is contacting a burr. When the bolt is turned on opening case is turning and the brass shaving is piled up on the right end of the scratch.
Coat the neck and shoulder of a loaded round with magic marker, load in the chamber and fire, If no mark from chamber, Time to coat a fired case and run through the die. May take a chamber or die polish to cure.
Good Luck in finding the problem then the cure.