I have a 7.7mm that my FIL 'brought back' from Japan. Gave it to me a short time before he past. Ammo can be somewhat pricy when found. Some ammo I use made by using 'fire formed' 30-06 cases and .303 Brit load data. Fires just fine in the rifle.
General Guts- can you get pictures of the markings? Mine has markings on top of the receiver in front of the chamber.
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