The French FAMAS was one of the first bullpup rifles to be adopted and built in large numbers by a military power. It was adopted by France in 1978 at right about the same time as the Steyr AUG was being adopted by the Austrian military. Bullpup rifles offered a short overall length without sacrificing barrel length, an advantage that seemed quite valuable for troops who were to spend significant amounts of time in vehicles, where space is at a premium. In French service, the FAMAS was also made the formal replacement for both the MAS-49/56 rifle and the MAT-49 submachine gun, thanks to its compact nature.
The FAMAS is interesting mechanically, as it is one of very few production delayed-blowback rifle designs (the other common one being the CETME/HK series). The FAMAS uses a lever-delaying system, which allows a very simple bolt and action mechanism. The F1 model (adopted by the French Army and still in use today, making up the bulk of FAMAS production) has a 1:12" twist to its rifling, effectively limiting it to 55 grain projectiles - and it also requires steel-cased ammunition to run reliably. The G2 variant (adopted in 1995 by the French Navy) changed to a 1:9" twist, introduced a full-hand trigger guard, and also uses NATO standard AR15 magazines instead of the proprietary 25-round magazine of the F1.
In the late 1980s a small number of semiauto FAMAS rifles were made by St Etienne and imported into the US by Century. Most people say 100-125 rifles, although serial number suggest this may have actually been 225-250 rifles. Regardless, they are quite scarce and expensive today.