Thank you for your replies. I know it was fired sometime pre 1969 by my mom to scare off a drunk at the front door, lol. True story. Dad always kept it and 7 shots together in a drawer, emergency protection I guess. Located serial numbers and all 3 match. Really like the folding hammer, that's neat!
I would guess that someone in history pryed the grips off and snapped each one in the process. Don't know a thing about "bore" or how to check it out. Date on hammer is Jan. 27, 85. would that be production date?