That's exactly what itis: Mannlicher Model 1895 straight-pull, built at Budapest. Hungary was a part of the Austro-Hungarian Empire at the time these rifles were built, not a national entity of its own, even though the paper money was written in almost a dozen languages.
This is an easy cartridge to make, can be converted from 7.62x54R very easily and quickly. Just open out the case-mouths and trim to the correct length of 1.98 inches. Your loaded-round length will be 3 inches precisely. You can use the same clips as with the 8x56R; there are some around and you can even find them with Adolf's eagle-and-swastika marking.
BARNES (COTW6) gives 48 grains of 3031 as a chrage for this one, using a 159-grain slug, or 45 grains of 3031 with a 227. Original bullet was a whopping great monster of a 244 which (thankfully) sems to be unavailable.
This is another cartridge which would profit from the C.E. Harris Universal load: 13 grains of Red Dot shotgun powder with a 180 CAST bullet for about 180 ft/sec.
Dies are scarce and expensive, although I do believe Trade-Ex stocks them. When I wanted to push case-necks back for my own Carbine, I just used the FL dies from my $25 LEE set of 8mm Lebel dies. Worked fine.
Once you have brass made up, likely you will be able to get aay just with neck-sizing. It's not likely you're going to run into another of these.
This would be a nasty little Bambi rifle: short, light, quick to get a sight with, super-quick to load or reload and enough power to flatten Mister Bull Moose with a single round.
These were the official rifle of the Austro-Hungarian Empire and, after World War One, they wee used by the successor states of Austria, Hungary, some in Italy, lots in Yugoslavia, a few in Romania, quite a number in Czechoslovakia until they standardised on Mausers, and they were used in Greece as well (war booty) and Bulgaria, where they had been the official rifle since 1903.
You have a real chunk of history there, and it's useful to boot.
I'd say you struck it lucky!
Hope this helps.
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