Hi Darryl,
Congraulations! A super rifle!
This rifle and the Brazilian M1922 are the first FN-made contract rifles after WW I around 1924-25. This was made for Yugoslavia at the time it called itself the "Kingdom of the Sebs, Croats and Slovenes", hence the strange "CXC" abbreviation of the left side of the receiver. Is it import marked? A few nice ones like this were imported by Century from Albania in the early 1990's, but others were brought home after WW II by GI's.
These rifles are heavily serialized, (like the Mexican 24's and Brazilian 22's) because FN did not have the manufacturing capability to do precision manufacturing until the advent of the M.1930
Regards,
John