Russian Special Forces have not given up on the underwater machine gun concept. The new Tula ADS has just been declassified and put on display at the Interpolitex 2013 expo. RT.com reports …

The weight of the machine gun with the grenade launcher is approximately 4.6 kg. The ‘ADS’ uses bullets of 5.45х39 mm at a firing rate of 800 shots/min with the aim range on a land of 500 m.   The rifle’s effective firing range underwater when using a specially designed cartridge is about 25 meters at a depth of 30 meters and 18 m at a depth of 20 m. The new underwater cartridge is externally very similar to standard 5.45×39 ammunition except for a different specially calculated bullet shape. The bullet length is 53.5 mm compared to an overall cartridge length of 57mm.   As compared to the Soviet underwater assault rifle APS that was designed back in 1970s, the new ADS is no less efficient when firing on land than a traditional Kalashnikov. Firing 5.66 mm caliber steel bolts, the APS with its non-rifled barrel is somewhat inaccurate on land. Out of water the APS’s lifetime was only 180 shots with an effective range of around 50 meters.   Completed in Tula in 2007, the ADS machine gun has undergone successful tests in naval special units in the Russian Defense Ministry in the North, Far East and the Black Sea. Rosoboronexport is promoting the new weapon for export.