The GP-25 Kostyor ('Bonfire'), GP-30 Obuvka ('Shoe') and GP-34 are Russian under-barrel grenade launchers for the AK-series of assault rifle. They were first seen by the west in 1984 during the Soviet Invasion of Afghanistan. The initial version was designated BG-15 Mukha ('Fly'), and was fitted under the barrel of AK-74 assault rifles. The main production version, the GP-25, has a different sighting system. The GP-30 was lightened and the redesigned sighting system was moved to the right.
The current Izhmash-made version, the GP-34, has an again redesigned sighting system on the right and features the following advantages:
- Reliability: It is designed and tested specifically for the Kalashnikov assault rifles, fits such assault rifles directly without any adaptors or forearm dismantling.
- Improved safety: The design prevents a round from moving within or falling out of the barrel, even if the muzzle looks down. The GP-34 features an additional mechanism (firing pin safety lever) to improve safety during loading.