First, I don't think that it's an 8 x 57 because I think the rifle is an Steyr-Mannlicher M95.
The Steyr-Mannlicher M1895 Carbine, a cut down version of the original M1895 rifle when the rifle, was rechambered from the 8x50Rmm cartridge to use the 8x56Rmm. Based upon the straight pull bolt of the Steyr Mannlicher, designed by Ferdinand Ritter Von Mannlicher (known for the introduction of the first successful clip fed rifle).
In 1895 the Austro-Hungarian Empire came out with the design that was to be used for much of the next century by one country or another. The M 1895 action was identical to that of the M 1890, except there was a thumbpiece at the back of the firing pin. The M 1895 rifle had a 30.1 inch barrel which gave the 8 X 50R bullet a velocity of 2030 fps. Sights were to 2600 paces. There was a carbine and a stutzen, both with 19.6 inch barrels which gave 1900 fps with the 8 X 50 R round. Their sights were shorter and went up to 2400 paces. The safety was simple and effective; a thumbpiece on the left side of the bolt locked the firing pin in either its cocked or down position. When locked down, the firing pin did not protrude from the bolt face, although when all the way down without the safety applied, the firing pin did stick out of the bolt face and could fire a cartridge. The rifle was slim and well balanced. The carbines were particularly light and handy.
After the war, the small Austrian and Hungarian armies continued to use the M95. In 1930 Austria re-chambered the rifles for a more powerful cartridge, the 8 X 56 M30. The rifles were called the M95/30. Hungary followed in 1931, calling the cartridge the M1931 and the rifle the 31M. The longer round put out a 208 gr. spitzer boat tail bullet at 2280 fps from the rifle length barrel. The groove diameter remained .329 inch and a .329 inch bullet was used. Base and rim were the same as the 8 X 50, so no change was needed in the bolt head or extractor. Rifles are much less common than carbines or stutzens since most of the rifles were cut down to stutzen length. Cut down rifle barrels have the front sight on a barrel band, and the rear is usually the longer rifle sight. Recoil in the 6.5 lb. carbines was pretty grim. Rifles chambered for the 8 X 56R are stamped with a large �S� on the top of the chamber, except that some, not all, Hungarians are stamped H instead. It is possible some rifles were re-chambered without receiving any special markings.