I think this is one of those “it fits so i’ll put it in there” jobs. I have a fired 8x58R Danish Krag case headstamped:
This was fitted with a lead cored GMCS RN FMJ bullet. I pulled it as I thought it was a put-together job, it has a “K” base mark. It has a curved cannelure that is not knurled. Is this some sort of Kynoch bullet or something else? I doubted it was original as I have an inert unfired HL 8x58R Danish Krag round dated 1928 and this has a lead cored CNCS Spitzer bullet.