The ADS amphibious rifle (Avtomat Dvukhsrednyy Spetsial'ny, Автомат Двухсредный Специальный, "Special dual-medium assault rifle") is a Russian amphibious assault rifle.
The ADS was built on the research and studies performed on the ASM-DT and previous underwater firearms, the first Russian dual-medium assault rifle; a problem with the ASM-DT was its use of specialized proprietary ammunition if it were to be used underwater, however, by 2005, TsKIB SOO had developed specialized supercavitating 5.45×45mm rounds that can be used underwater, and as such, the ADS uses these rounds. The weapon entered service in August 2013.
The ADS is based on the A-91 assault rifle. The weapon is fitted with a 40mm grenade launcher up front which can fire off various VOG-25 grenades, though no mention of the ability to fire specialized underwater grenades is made. The weapon has a forward ejection tube, so cartridges are ejected forward of the shooter, preventing any danger of hot brass being flung into the shooter's face.