I saw a video link on Youtube about using silly putty as a shotgun load and couldn't resist. (As you'd expect, it shatters just like when hit with a hammer) Next thing I knew I was hypnotized watching chains of related videos of gun enthusiasts making unconventional shotgun loads... shotting a handful of dimes into a board... that sort of thing.
Then there were some incendiary shotgun loads... "dragon's breath" I think the name was. Cool looking but without much practical application. (Assuming that burning down your own garage is not your objective.)
Then there was a video comparing two brands of 'sawed off' shotgun. They are not sawed off, which would be illegal. They are manufactured with a short barrel in the first place, and thus legal in some way where you have to pay a $5 tax.
So I am watching this guy walking around with perhaps the most fearsome personal arm in the world—a concealable shotgun—shooting pumpkins and such.
But watching the guy I wasn't very riled up about this "how the heck is that legal???' weapon because it can only hold three shells, loaded from two different sides of the gun. Half the video was watching the guy load the gun over and over. So it was apparent that a standard 6-shot .38 revolver pistol was, in some ways, more dangerous than this de facto sawed-off shotgun.
The whole "assault weapon" thing is kind of a joke since handguns are what kill people day in, day out. But one thing in the original AWB that made real sense to me was limiting the capacity of shotguns. (I think it was a six shell limit?)
The shotgun is an ideal indiscriminate mayhem gun... it is designed for shooting flocks of birds and fast-moving animals and the logic is similar for flocks of people.
What keeps the shotgun from being the gun of choice for maniac sprees is, near as I can tell, capacity.
But instead of getting into nonsense like flash suppressors and bayonet mounts, I would be more inclined to limit the capacity of everything. All rifles and handguns.