GP-25 grenade launcher
40 mm GP-25 under barrel grenade launcher mounted on an AK-74 assault rifle (airsoft replica GP-25).
Type	Grenade launcher
Place of origin	Soviet Union
Service history
In service	1978–present
Used by	See Users
Wars	War in Afghanistan Soviet–Afghan War Transnistria war First Chechen war Second Chechen War Russo-Georgian War Syrian Civil War Russo-Ukrainian War[1] Yemeni Civil War (2015–present) Saudi Arabian-led intervention in Yemen Saudi–Yemeni border conflict (2015–present)
Production history
Designer	TsKIB SOO
Designed	1966–1978
Manufacturer	Kalashnikov Concern STC Delta Arsenal AD Zastava Arms
Produced	1978–present
Variants	GP-30, GP-30M, GP-34
Specifications
Mass	1.5 kg (3.31 lb) (GP-25) 1.3 kg (2.9 lb) (GP-30) 1.4 kg (3.1 lb) (GP-34)[2]
Length	323 mm (12.7 in) (GP-25) 275 mm (10.8 in) (GP-30) 315 mm (12.4 in) (GP-34)[2]
Barrel length	120 mm (4.7 in)
Cartridge	40 mm internal propellant caseless ammunition (CL)
Caliber	40 mm
Action	Closed system, single-shot
Rate of fire	20 rounds/min area suppression[2] 5–6 rounds/min aimed shots[2]
Muzzle velocity	76.5 m/s (251 ft/s)[2]
Effective firing range	Sights adjustable 100 to 400 meters[2]
Feed system	Muzzleloader
Sights	Notched quadrant sight

The GP-25 Kostyor ("Bonfire"), GP-30 Obuvka ("Shoe") and GP-34 are a family of Russian 40 mm under-barrel muzzleloaded grenade launchers (Granatomyot Podstvolnyj) for the AK family of assault rifles. They were first seen by the West in 1984, during the Soviet Invasion of Afghanistan. The GP-30 was lightened and the redesigned sighting system was moved to the right.

The current Izhmash-made version, the GP-34, has a further-redesigned sighting system located to the right side of the weapon 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.^[2]
• Improved safety: The design prevents a round from moving within or falling out of the barrel, even if the muzzle is pointed down. The GP-34 features an additional mechanism (firing pin safety lever) to improve safety during loading.^[2]

Development

Development of a grenade launcher for the AKM assault rifle began in 1966 at the Sporting and Hunting Arms Central Design and Research Bureau. Development continued into the 1970s, and in 1978 it was accepted into service.

The GP-30 first entered service in 1989, and is intended for use with the AK-100 series of assault rifles.

The GP-34 is designed to be a universal service model that can be fitted to the AKM / AKMS, AK-74 / AKs-74, AK-74M, AK-101, AK-103, and AN-94 rifles.

• 
  GP-25 grenade launcher
• 
  GP-30M grenade launcher
• 
  GP-34 grenade launcher

Description

The grenade launchers are similar in appearance and fire the same 40 mm caliber ammunition together.

The GP-30(M) is a stripped-down model grenade launcher, consisting of a very short, 40 mm rifled barrel in front of a basic trigger mechanism with minimal hand grip. On top of the barrel is mounting gear to attach the weapon under the barrel of an AK-series assault rifle, from where it is designed to be fired.

The barrel has a service life of about 400 rounds.

Ammunition

40 mm VOG-25 7P17 round of GP-25 grenade launcher

The ammunition family consist of 40 mm internal propellant caseless ammunition, cartridges containing the propellant inside the warhead instead of a cartridge case, based on the same High-Low System developed by Germany in late World War II to keep recoil forces low without a rocket or other type of recoilless weapon back blast. The rounds feature a special type of driving band which allows for muzzle loading, featuring a sub-caliber diameter when loading, which flanges outward to full-caliber and engaging the rifling inside the barrel when fired. This differs from the more traditional two piece casing-and-projectile design of the comparable American 40x46mm LV cartridge used in breech-loaded grenade launchers, such as the M203.

When firing, a round is first muzzle loaded into the barrel, the weapon is aimed, then the self-cocking trigger is pulled to fire the weapon. This fires the percussion cap at the base of the round which triggers the internal nitrocellulose propellant. The hot expanding gas from the propellant is forced through vents at the base of the shell, propelling it through the barrel and at the same time forcing the driving band to flange outwards to engage with the twelve rifling grooves. The rifling imparts stabilizing spin to the projectile.

Users

•  Angola
•  Algeria^[4]
•  Botswana^[5]
•  Brazil: Used by Caatinga infantry^[6]
•  Bulgaria: Made under license by Arsenal AD as the UBGL^[7] and the UBGL-1.^[8]
•  Burundi^[9]
•  Congo-Kinshasa
•  Cyprus
•  Georgia: Made by STC Delta.^[10][11]
•  Greece: Used for the AK-74M.
•  India^[12]
•  Indonesia: Mobile Brigade Corps^[13]
•  Iran : Used by IRGC
•  Lithuania: Lithuanian Armed Forces^[14]
•  North Korea^[12][15]
•  Pakistan
•  Russia^[12]
•  Serbia: Made under license by Zastava Arms as the PBG – 40 mm^[16] and the PBG 40 mm M70.^[17]
•  North Macedonia
•  Syria: Uses both GP-25s and GP-30Ms.^[18]
•  Ukraine^[12]
•  Vietnam

See also

• BS-1 Tishina
• QLG-10
• RGM-40 Kastet grenade launcher is a stand-alone version of GP-30 grenade launcher
• Wz. 1974 Pallad grenade launcher

References

• Koll, Christian (2009). Soviet Cannon – A Comprehensive Study of Soviet Arms and Ammunition in Calibres 12.7mm to 57mm. Austria: Koll. p. 397. ISBN 978-3-200-01445-9.

External links

Wikimedia Commons has media related to GP-25.

• Modern Firearms
• Technical data, instructional images and diagrams of the GP-25 (in Russian)
• Differences between GP-25, GP-30, GP-30M and GP-34 (in Russian)