Now, as the Governator might point out, there's clearly no need, personally, for such a thing.
Tell "Ahhh-nold" there's no need for the blood and guts type movies like he's made. There's no need for pornography too, but these things seem to have no problem getting 1st amendment protection. There are thousands of academic studies showing that long term exposure to voilent media causes violent behavior, but all types of violent media enjoy Constitutional protection regardless. Go figure...
The right to keep and bear arms made no distinction between what types of arms or calibers.
I've never had the chance to shoot one of those things, but I'll bet it's a real hoot!