CXC Model 1924 Mauser

This my CXC Model 1924 Mauser, I bought the rifle years ago at an auction in Germany. Any information or opinions about the rifles history and the markings are welcome and would be greatly appreciated.

'CXC'....Kingdom of Serbs, Croats, and Slovenes. Nice M24!

These are the last detailed pictures of all the markings I found on my CXC Model 1924 Mauser without disassembling the rifle.

Very nice the early Yugoslavian rifles are very interesting, and this one appears to be in great shape (especially when compared to some of the other ones I have seen).

I understand that Serbian Cyrillic script was one of the two official scripts used to write the Serbo-Croatian language in Yugoslavia since its establishment in 1918, the other being Latin script.

Does anybody know why they used the Serbian Cyrillic letter Д (Latin translation = D) and the Latin letter K (Cyrillic translation = К​) as an inspection or proof mark and what does it mean? Can you find the same marking on other known Yugoslavian Model 1924's made before or even during WW2?

If I'm not mistaking there were 3 types of Yugoslavian Model 1924's. I found this online: "The standard gun was produced in three variations: One rifle and two carbines. All three were the same length and weight and the differences are minor. Both carbines have two sling swivels on their lower barrel band (like a vz.24). Type 1 carbines have a turned down bolt handle for cavalry. Type 2 shares the rifle’s straight bolt and were intended for artillery or engineering units." Source: http://candrsenal.com/rifle-serbian-mauser-model-1924/

Is it possible that my CXC Model 1924 is a "Type 2" for artillery or engineers as described? Please correct me if I'm wrong, I'm here to learn.

What's the hole in the stock for? A rope sling?

This is just a guess for the 'K' inspection proof. It could stand for Konig (king in german) or краљ which is king in Serbian.