 Most heavy barrel FALs are equipped with bipods, although some light barrel models were equipped with bipods, such as the Austrian StG58 and the German G1, and a bipod was later made available as an accessory.Among other 7.62×51mm NATO battle rifles at the time, the FN FAL had relatively light recoil, due to the user-adjustable gas system being able to be tuned via a regulator in fore-end of the rifle, which allowed for excess gas which would simply increase recoil to bleed off.The regulator is an adjustable gas port opening that adjusts the rifle to function reliably with various propellant and projectile specific pressure behavior, making the FAL not ammunition specific.