No one's made it yet. I figure if I mention this concept enough times, people will pick up on it, and when it turns into a chant, one of the makers will listen.

As far as regualtion, won't be any where near as bad as it is for a traditional double rifle, becuase I'm talking an over-under. Sure, different ballistics, but I'm pretty sure that if the sights will thump a rabbit with the .22 at 25 feet, the .30 caliber will hit in the heart-lung area on a deer at 150 feet, which is a lot longer than I'd ever want to push a .410 slug.

If you wanted to get very fancy, set up the front sight like a bow sight, with two seperate and distinctly colored fiberoptic dots for each of the barrels. But it would mean a very tall front sight, not sure if we want that.

The other option is to glass it using a see-though mount, say 2x or 3x, and zero the optics for the .30 caliber, while the iron sights are zeroed for the .22.

Different zeros is the one potential pitfall I can see with this, but nothing that can't be worked out. As far as actual, in the field windage compensation, for most hunting distances, it isn't as big a deal. This is a survival/truck gun, not something for bagging big sheep at 800+ yards.