yes, that flat grind is unusual, but it looks like it also has electro pencil numbers on the safety. That's a clue. I don't know that I've seen a flat grind Yugo like that. I've seen it on postwar rework Romanian Vz.s I believe. Remember that the K98k of the 1940s - 50s was the same as the AK/AKM of today. Every 3rd world country probably used them, and reworked them, thus there are plenty of variations of assemblies and reworks, etc. It would be nice to have the rifle it came out of!