Does anyone know details of this rifle grenade? It possibly is Soviet post war ( experimental ? ). Unfortunately I have no dimensions but diameter is approximately 30mm. There are 3 small studs to fit in rifling grooves on the launcher ( 3 grooves like in Diakonov grenades but smaller diameter ).
Is it this one?
GSN-19 "Kanarejka" grenade launcher installed on 5.45mm AKS-74UB assault rifle, grenade launcher sight in folded position. Note that the host gun is fitted with rare 20-round magazine. The leather cover on the gun's forend is used to cover grenade launcher mounting interface when it is not installed on the host gun.
Caliber: 30 mm
Overall length: n/a
Weight: 2 kg unloaded (5,4 kg when installed on AKS-74UB, along with sights and silencer on the host gun)
Effective range: up to 150-200 m (400 m maximum)
Armour penetration: 15 mm
The BS-1 "Tishina" (Silence) grenade launching system is one of most interesting and impressive weapons that were developed for Soviet Spetsnaz (Soviet Army Special Operations forces). This system was adopted in 1970s, to replace previously used stand-alone slienced / flash & noiseless 30mm grenade launchers known as "device D". The idea behing "noiseless" grenade laucnher was to hide the sound and flash of the grenade launch and thus give the shooter (and his comrades) more chances to escape after a sucessful diversion behind enemy lines (main targets for Spetsnaz during the Cold War were tactical nuclear missile launchers, C&C inatallations and equipment, fuel and ammunition storage facilities and parked tactical aircrafts). Original BS-1 system included the 7.62mm Kalashnikov AKMS assault rifle with PBS-1 silencer, subsonic 7.62x39 US ammunition, 30mm GSN-19 underbarrel grenade laucher and grenade launching sight. When, during late 1970s, Soviet army switched over to 5.45x39mm ammunition, 7.62mm AKMS assault rifles with PBS-1 silencer were replaced with 5.45mm AKS-74UB compact assault rifles with PBS-4 silencers. The original GSN-19 grenade launcher was slightly revorked, mainly to use different launching ammunition (based on 5.45mm rather than 7.62mm blanks). Other changes include different mounting brackets to better suit AKS-74UB compact assault rifles. These weapons are still in limited use with Spetsnaz elements of Russian army and probably some others armies of ex-USSR countries.
The GSN-19 silent (flash and noiseless) grenade launcher is unusual in the fact that it is both muzzle- and breech-loded. The standard projectile is a specially designed AP-I (Armour Piercing - Incendiary) grenade with pre-engraved rifling. The warhead is designed to penetrate hulls of tactical ballistic missile launchers, aircrafts, C&C equipment, and then cause enough damage to render the target inoperative. The grenade has no propelling system in itself. The launch is performed by special blank cartridges, which are loaded into detachable box magazine (holding 8 cartridges in 7.62mm based version or 10 cartridges in 5.45mm based version). Cartridges are fed into the chamber by manually operated rifle-type rotary bolt action mechanism. To achieve the noise- and flash-less launch, blank cartridges are discharged into the limited volume breech, which is fitted with movable telescopic piston at the front. Upon discharge, this piston violently pushes the grenade, loaded into the muzzle part of the launcher, out of the barrel, and then stops and seals the expaning powder gases inside the rear part of the launcher's barrel. After a short while perssure inside drops to safe level and gun can be reloaded by operating the bolt (to extract spent blank and load a fresh launching cartridge) and then loading the new grenade from the muzzle. Loaded grenade is held in the barrel by special springs. The muzzle velocity of the 30mm grenade for 7.62mm version is quoted as "above 100 m/s", for 5.45mm version it is listed as 175 m/s. Grenade launcher is attached to special brackets, welded to the host assault rifle. To fire GSN-19 accurately and comfortably, host rifle is equipped with special folding grenade launching sight (attached to the base of standard rear sight) and with removable rubber recoil-absorbing buttpad.
