The FAMAS F1 is the original version of the FAMAS rifle, and the standard service rifle of the French Army. The F1 can be distinguished by its smaller trigger guard, ribbed barrel, and its straight, 25-round French service magazine.
Trivia: The FAMAS F1 has issues with brass cased 5.56×45mm ammo that other NATO countries use, which can create over-pressure in the FAMAS and result in malfunctions. The FAMAS F1 instead primarily uses steel cased 5.56x45mm ammo. The FAMAS G2 can function correctly with both steel and brass cased ammo however.
The FAMAS G1 is an intermediate version of the FAMAS between the FAMAS F1 and the FAMAS G2. It can be distinguished by having the magazine well of the F1 and using its straight 25-round magazines, but also having a new enlarged trigger guard that is also used on the G2. The G1 did not see widespread production.
The FAMAS G2 is the current version of the FAMAS rifle. It is the standard rifle for the French Navy; the French Army still used the FAMAS F1 as the their main service rifle prior to transitioning to the Heckler & Koch HK416F. The G2 uses the G1's improved trigger guard and forend, but has a redesigned magazine well for the use of NATO STANAG magazines. The barrel of the G2 was changed to a 1:9 inch rifling twist from the original F1's 1:12 inch rifling twist to allow the G2 to utilize a wider range of NATO 5.56 ammunition, such as the older 55 gr M193 type ammo and the newer 62 gr SS109 type ammo. They can be seen with both smooth barrels and ribbed rifle grenade firing barrels.
The FAMAS FÉLIN is a variant of the FAMAS outfitted to be used in conjunction with the FÉLIN combat system. The most notable difference is the replacement of the integral carry handle with a lower profile scope mount for mounting optics, which when used as part of the FÉLIN system would mount a large day/night/thermal video sight capable of transmitting the feed to the soldier's helmet mounted eyepiece. The final production version of the FÉLIN features a forward vertical grip which houses the controls for the system, and has lengthened and bent bipod legs.
Also intended for use alongside the FAMAS FÉLIN is the FAMAS Valorisé (meaning "upgraded"). This variant was intended for use in FÉLIN equipped units for use by soldiers not requiring the actual full FÉLIN combat system. As such, this variant has the same low profile sight rail and new bipod, but omits the second grip and was intended to be fitted with a 4x optical day sight as standard. In the past variants of the FAMAS with a low profile scope rail have been referred to as the FAMAS Surbaissé (meaning "lowered" in reference to the scope mount), however promotional material from the manufacturer GIAT states that the FAMAS Surbaissé is the core weapon (or possibly just component) on which the FÉLIN and Valorisé rifle variants are based.
