No, that’s neither a misprint nor an oxymoron. This is an accurate description of a few models developed by TsKIB (Central R&D Bureau for Sporting Guns, Tula, Russia) for the sake of professional fur hunters. The idea was that trappers needed a combination gun, but a combination gun is by definition two single shots in one stock. What do you do if you want a quick follow-up shot with the same caliber? A pack of young designers were let loose on the problem, and here are some of the solutions they came up with:
MTs 27 was a combination of a bolt-action big-game rifle with a small-bore semi-automatic shotgun. It could fire two 9.3x53R rounds (the 7.62 Mossin case necked up to 9 mm) from the over barrel, and three 20-gauge shells from the under barrel.
MTs29 is a single shot bolt-action shotgun above, and a 8-shot semiautomatic .22lr rifle with the action from the Soviet copy of Browning Auto22, known as “Sport” with a magazine in the stock, below.