John, I've owned several, all stack barrel rifles. I believe they are more correctly called combination rifles, rather than double rifles. though they have two barrels, both rifled. All the ones I've owned have been German, and are fine walk about hunting rifles for general bag, and make a fine back up for a serious main double if one of the barrels is uig enough to handle the big boys. I had one that was 9.3X74R on the bottom, and a .22 hornet on top. I used that little rifle for years in the New Mexico mountains, hunting Elk, Muledeer, and Coyotes! HANDY!!!!!!!!!!!