The Steyr IWS 2000 is an Austrian semi-automatic anti-materiel rifle produced by Steyr Mannlicher. IWS stands for Infantry Weapon System. It is actually a smoothbore weapon, like many modern tank guns, and not a true rifle but this can help accelerate projectiles and increase ballistic effectiveness. It fires a 15.2×169mm armor piercing fin stabilized discarding sabot round (207 mm long), and is the first man-portable rifle to use this type of ammunition.
The first variant of the weapon was the AMR 5075. AMR stands for Anti-Materiel Rifle. It used a 14.5 mm armor-piercing fin-stabilized discarding sabot round (200 mm long). The projectile was a solid tungsten fin-stabilized dart with a body diameter of 5.56 mm.
Other variants are expected with the weapon still being under development.