An introduction to the F2000 in Modern Warfare 2 multiplayer. The FN F2000 is a 5.56x45mm NATO bullpup assault rifle, designed by FN Herstal in Belgium. The F2000 is a modular weapon system; its principal component is a compact 5.56x45mm NATO-caliber assault rifle configured in a bullpup layout. The F2000 is a selective fire weapon