Steyr IWS 2000

The Steyr Infantry Weapon System 2000 (IWS 2000) is a single-shot, bolt-action anti-materiel rifle produced by Austrian firearm manufacturer Steyr Mannlicher. Unlike other anti-tank rifle designs, the IWS 2000 has a smoothbore barrel. This facilitates higher projectile velocities and allows a longer barrel service life, but the lack of rifling-induced gyroscopic spin-stabilization requires the IWS 2000's projectile to have aerodynamic stabilizing fins instead, making it an armor-piercing fin-stabilized discarding-sabot projectile.
The first variant of the weapon was the proposed AMR 5075 (AMR standing for anti-materiel rifle). It was to fire the same type of ammunition as the IWS 2000 and to use a 5-round detachable box magazine. However, that version did not pass the proposal stage.