Might as well spray paint hydro dip that piece of shit. It looks like they made it in a car shop to begin with and there's not really much in the way of moving parts to fuck up. I bet operating it takes longer than reloading a double barrel.
I don't think the center is a barrel. The more I look at it the more I think you're supposed to manually revolve the barrels. It seems like the top one might be designed to get hit by the external striker mechanism. But maybe there's some system inside the gun we can't see.