No answers but observations and opinion.
Several pricey features on this gun. Chopper lump barrels, POW grip, case colours, rebated frame and forearm metal. Case colours on frame mostly worn off, but untouched on forearm metal. Odd wood colour match(?) between stock and forearm. Chopper lump joint left uncleaned.
I suspect the frame bottom will look similar to pic in the Kawaguchiya-Hibiki-Miroku threads. I can't imagine there were too many 1955 - 1980 Japanese chopper lump barrel makers.
Don't know, but I suspect you'll find this shotgun is "son of" or "kissing cousin" to the K-H-M production.
