It's used for hunting, and he can change caliber depending on what game he's stalking.
It even has sights in the scope.
It's amazing what his mind can do with a bit of foam packing, a paper towel tube, a toilet paper tube, q-tips, paint, and tape. He says he's sorry he didn't take pictures for a tutorial. =)
(Don't worry, it's not loaded, safety's on, and the chamber's open. hee hee)
He says he's bringing home venison for dinner. Yay!!!