Wow, that's rough. Kind of an old way to get in trouble for making airsoft guns. Gun replicas that load compressed gas shells and fire with a firing pin are a mistake as old as that Remington replica that shot blade bullets. You'd have thought that ASGK would have required that the carousel holes were slightly smaller than the diameter of the real shell to prevent the loading of real bullets. When I visited Japan, I kept hearing that ASGK had become an old boys club that lacked significant engineering to do much testing. I'm wondering if it has atrophied to a point of uselessness.
I'm guessing that the modification to shoot live rounds isn't to rebore the barrel, but to remove it entirely. You gotta wonder what happens to the frame after shooting S&W 500 though.
Want nearly free GBB gas?