The OTs-14 Groza (Russian: ОЦ-14 "Гроза", lit. '"Thunderstorm"')[1] is a Russian selective fire bullpup assault rifle chambered for the 7.62×39 round and the 9×39mm subsonic round. It was developed in the 1990s at the TsKIB SOO (Central Design and Research Bureau of Sporting and Hunting Arms) in Tula, Russia.[2]