I recently purchased a Danish Krag carbine.  There is not a stock disk on the right side of the butt stock, there is no evidence that there ever was.  Instead, there are the deeply stamped letters FS.  They are approximately .75 inches high. 

I  have not seen these markings before and wondering if anyone else has and if you might be able to give me some information about the markings.  The stock is a carbine stock, with serial number on the underside of the butt stock and a faint danish crown proof stamp on the left side of the stock in front of the receiver. 

I will try to figure out how to resize the photo I have of it so I can post it.

Thanks,
Tom