i knew a guy about 25 years ago that attached a glass pack muffler to the muzzle of a shotgun. It was by no means silent but the report made you go Hmmm, what the heck was that? It did not sound like gunfire. It was a weird sound.
I would *think* that if you were shooting slugs, then yes you probably could make one. For using shot, I would believe that it would be very difficult to get one to work. I have never heard of nor seen one though.