The Czechoslovakian ZB vz26, was issued to the Czechoslovakia army and used the 8x57mm S ball (~150grains) of WW1.
The ZB vz30 used the sS ball (~198grains), the German standard of WW2.
The reference is; The Bren Gun Saga By Dugelby, T. B., Book - 1999,
The kar98 shown with the muzzle brake is chambered for the 8x63mm machine gun ammunition, and has a 4 shot magazine if I remember correctly.