The installer likely over tightened the barrel a couple of degrees or the notch and thread timing were slightly off.

Widening the notch slightly would be an easy fix with a file, if the barrel were off the action.

Very much Mavt's call. Frustrating that it wasn't done correctly and still isn't quite right.

IMHO - If it were mine, it is easily fixed with a little stone work on the right-side of the extractor claw.

I would not want to send it back to the installer and lose the use of a utility Krag for months.

(Oops, 'mavt' fixed it. Well done You! Give us a Range Report, soon).