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"The 20 mm model F2 cannon is a naval self-defence weapon used by the French Navy. It was developed from the GIAT M693. It fires 20 � 139 mm shells originally developed for the Hispano-Suiza HS.820 series of cannons. It also equips land and air vehicles of the French Army.
In the French Navy, the need for a 20 mm gun newer than the 20 mm Oerlikon began to grow significantly during the 1980s. DCN and GIAT were selected to design the 20 mm F2 gun, which is essentially a naval version of the M693 gun used by the French Army and exported.
The 20 mm F2 gun is a single-barrel gun with two boxes of 160 shells on each side of the weapon. An electric control system allows a choice of three firing modes: single shot, eight-round burst, or free fire. It operates by gas impingement. The dual feed belt system allows the gunner to select the appropriate ammunition for the target almost instantly. The electric trigger is positioned in the gunner's right hand. After each shot, the empty shell is ejected from the bottom of the weapon.
The gun is operated by the gunner's body, which is strapped to the weapon. Firing is guided by the same sighting optics as those used on the 40 mm Bofors and 20 mm Oerlikon.
Specifications
Weapon length: 2.60 m
Weapon weight: 70 kg
Rate of fire (max): 700 rounds/min
Muzzle velocity of explosive shell: 1,050 m/s
Muzzle velocity of sub-calibre armour-piercing shell: 1,300 m/s
Muzzle velocity of calibre armour-piercing shell: 1,070 m/s
20 mm explosive ammunition
Sub-calibre or calibre armour-piercing ammunition
Performance
Against light armour: up to 700 m (calibre armour-piercing).
Against light armour: up to 1,000 m (sub-calibre armour-piercing).
Against personnel: up to 2,000 m (neutralisation).
Against personnel: up to 1,200 m (destruction).
Against aircraft: up to 1,500 m[3].
It is manufactured under licence in South Africa by Denel Land Systems under the name GI-2 (en).
Naval
The F2 gun has been exported to Belgium (Tripartite minesweepers), Indonesia (Tripartite minesweepers), Malawi (Kasunga), the Netherlands (Tripartite minesweepers), Pakistan (Tripartite minesweepers), and Saudi Arabia (NAJA 12 class).
In the French Navy, they are used on the following ships:
The Charles de Gaulle nuclear aircraft carrier
Mistral-class amphibious helicopter carriers
Horizon-class frigates
La Fayette-class frigates
Flor�al-class frigates
Georges Leygues-class frigates
Estienne d'Orves-class avisos
Eridan-class minesweepers
Audacieuse-class patrol vessels (P400)
Dumont D'Urville
Jacques Cartier
La Grandi�re
Rapi�re
Hallebarde
Monge
Aircraft
It is used on certain helicopters such as the Puma of the French Army Light Aviation.
It is the main weapon of the Denel AH-2 Rooivalk attack helicopter of the South African Air Force.
Wiki.
I don't have a plan, and for good reason: it's still in service with the navy. The design is based on photos, freehand if you will.
I started with the two shell magazines, which gives me a good basis for the measurements and proportions for the rest.
