Denel NTW-20

The Denel NTW-20 is a South African anti-materiel rifle or large-calibre sniper rifle, made by the Denel company. As with other weapons of this type, they can be used for counter sniping, ordnance disposal (shooting explosive ordnance from a safe distance) or against enemy radar installations, communication equipment, parked aircraft, fuel storage facilities, vehicles or personnel.

Features
The NTW is one of the few firearms in existence that allow the changing of the caliber without completely disassembling and reworking the weapon. Switching between the two calibers (20mm and 14.5mm) requires changing the bolt, barrel, sighting gear and magazine. This can be accomplished simply in the field without specialized tools. The magazine protrudes from the left side of the receiver. The NTW can be disassembled and packed into two backpacks for carriage. A muzzle brake is fitted on the end of the barrel which absorbs an estimated 50%-60% of recoil. This is further supplemented by a buffered slide in the receiver. The NTW is in service with South Africa and an unnamed country in Southern Asia.

20 mm

 * Cartridge: 20x83.5 mm
 * Operation: manual bolt action
 * Feed: 3-round box-type, detachable magazine
 * Weight, empty: 26 kg
 * Overall length: 1,795 mm
 * Rifling: 1 full turn in 560 mm
 * Length of barrel: 1,000 mm
 * Muzzle velocity: 720 m/s
 * Muzzle energy: 28,500 J
 * Effective range: > 1,500 m

14.5 mm

 * Cartridge: 14.5x114 mm Russian
 * Operation: manual bolt action
 * Feed: 3-round box-type, detachable magazine
 * Weight, empty: 29 kg
 * Overall length: 2,015 mm
 * Rifling: 1 full turn in 406 mm
 * Length of barrel: 1,220 mm
 * Muzzle velocity: 1,080 m/s
 * Muzzle energy: 30,675 J
 * Effective range: > 2,400 m

Influence

 * The S2 AM sniper rifle in the video game series Halo was based on the NTW-20, but with the addition of semi-automatic capabilities, slightly increased magazine size and location of the magazine well. It uses 14.5x114mm armor-piercing fin-stabilized discarding sabot rounds (APFSDS), similar to the real-life Steyr IWS 2000 anti-material weapon.