One Cartridge the picture of the  box and clip are pictured for reference only

One Cartridge, Not a Box: 8x56Rmm Austrian / Hungarian Mannlicher cartridge produced in 1938 in Austria from at the Wollersdorf Staats-Munitions Fabrik.
Has original 1938  HeadStamp with Eagle Warbird over Swastika symbol on Headstamp. Please note: This is not the Rimless Mannlicher-Schoenauer Sporting Cartridge.

For Clips to the Austrian Model 95 straight-pull bolt action Steyr Cavalry rifle, see below in retated items..

History of the 8x56Rmm Austrian / Hungarian Mannlicher cartridge:
The 8x56Rmm introduced in 1930 to replace the older 8x50Rmm Austrian / Hungarian Mannlicher cartridge.
The "Rimmed" 8x56Rmm Austrian / Hungarian Mannlicher cartridge (designated the M30 in Austria, and the M31 in Hungary) and was developed  for the Austrian Solothurn machine-gun, the Hungarian Model 35 Mannlicher and also for the Austrian Model 95 straight-pull bolt action Steyr Cavalry rifle.
Please note!  This is not the Rimless Mannlicher-Schoenauer Sporting  Cartridge