We recently came across an old pistol when going through a family members belonging that had passed. It appears to be a pump 22 in a pistol version. The receiver looks to be a takedown and the barrel is short, around 8 inches. It has a pistol grip with an original pistol Backstrap frame that does not appear to be cut down from a shoulder stock. The barrel is crowned and has a front sight so does not appear cut down either. I have never seen anything like it. Anybody know what this is?