While you are on the site, in your browser find and click "Add to Home Screen" A CGN beaver app icon will then be created to your phone that is directly link to the site.
Note: This feature may not be available in some browsers.
I think you might mean the Thunder 5? ( http://www.thunder5.com/docs1.html ) They're prohibited, but some might have made it in before the cut-off. I've fired one, and I wasn't really impressed; it had the world's worst DA trigger-pull.
I have never heard of the "Big Thunder" revolver, and a Google search did not educate me any.
Magnum Research makes the BFR in .410 three inch (also will shoot .45 long Colt). Comes with a choke tube and a wrench, and a ventilated rib is optional. Great for skeet! I think that Wild West carries the BFR line.