Nope. FALs were made in various old rounds, such as 7.92x33mm and 7x45mm, as well as .223 and .308 originally. DSA produced .260 remington and .243 versions, though. I saw once on FAL files that a .35 caliber round based off of the .308 was made for it.
However, I'm still waiting on the .45 caliber version based off of the .308 case.