There is a reason. The Yugoslavs first bought FN Model 24's from Belgium, part of an arms buying relationship that also included FN Model 1922 pistols and Browning automatic rifles.
But FN had obtained the license for a slightly earlier Mauser that used a different breeching than that finalized as the Model 1898, and that is what they made as a commercial military called the Model 24. Those rifles were sold to a number of countries, including Yugoslavia. After WWII, the Model 24 rifles were upgraded and called the Model 24/47, the latter number being the year the upgrade was approved.
Yugoslavia also bought the machinery and tooling from FN so they could make the Model 24 rifles in-country. It is that tooling that was used in the immediate post-WWII period to manufacture the M48 which, naturally, copied the FN Model 24.
To confuse things further, 1924 was a banner year for national rearmament; every country seemed to want to upgrade is old weaponry to the new era of bolt action rifles, as exemplified by the new Mausers, which were considered the height of military small arms progress, notwithstanding that Germany had lost the war. The new nation of Czechoslovakia began manufacture of the VZ-24 using the standard Model 98 action. In Belgium, FN cranked up their production lines to turn out their own Model 24, and in Germany, Mauser got into the arms race later, but also called their commercial rifle the Model 24.
But I am puzzled about the "intermediate" ring size. The receiver ring of the "intermediate" 24/47 and 48 is the same size as that of the G/K 98.