; Appears to me, the recoil plate on the right side set back from an overload. They tried to push the recoil plate out after removing the screw and failed, so attempted to grind a groove around the shield holder and failed to loosen it enough to remove it for repairs. They then put the gun back together and to sell it as-is.
; It appears to me, if that barrel is fired, the primer will set back and lock up the gun.
; Just a guess.