Hello Oleg

My barrel flats are marked 67/49.
no marks onthe barrels to load information.
the rifle barrels are not marked nitro proofed.
But the shotgun barrel has the nitro proof stamps on it.
I do not know why the rifle barrels are not marked??
This was my question originally on the forum if this caliber was a blackpowder load or a nitro load originally. Do you know what these loads started out as??
I know the 9.3x72r started as blackpowder and later was loaded nitro.
thks
ralph