Some more things, I'm noticing:
It doesn't look like the entire bolt can rotate with the way it fits in the receiver. Does only the front portion rotate to lock up?
It's got sights, which is odd since it seems like none of the three barrels are in line with them.
I still think it's some sort of shotgun for use with .22 shotshells but if that's the case, the sights weird me out. It's gotta be pretty heavy too, eh? That's a lot of steel in the barrel