How a VSS Vintorez Works

The VSS (Russian: Винтовка Снайперская Специальная, Vintovka Snayperskaya Spetsialnaya or "Special Sniper Rifle", GRAU designation 6P29), also called the Vintorez ("thread cutter"/"tap"), is a suppressed sniper rifle that uses a heavy subsonic 9×39mm SP5 cartridge and armor-piercing SP6 cartridge. It was developed in the late 1980s by TsNIITochMash and manufactured by the Tula Arsenal. It is issued primarily to Spetsnaz units for undercover or clandestine operations, a role made evident by its ability to be stripped down for transport in a specially fitted briefcase.

The overall operating principle and sound suppression system used on the VSS are derived from the AS assault rifle. The VSS is a gas-operated select-fire rifle. It has a long-stroke gas piston operating rod in a gas cylinder above the barrel. The weapon is locked with a rotating bolt that has 6 locking lugs which engage appropriate sockets machined into the receiver. The VSS is striker fired. It features a cross-bolt type fire selector switch located behind the trigger, inside the trigger guard; the safety lever and the charging handle resemble those used in Kalashnikov weapons.

The weapon has an integral suppressor which wraps around the barrel. The barrel itself has a series of small ports drilled in the rifling grooves, leading into the suppressor which slows and cools the exhaust gases. The suppressor can be easily removed for storage or maintenance, but the VSS should not be fired without the suppressor. The weapon's integral suppressor has a length of 284.36 mm and a diameter of 35.86 mm.

The skeletonized wooden stock is a more rounded version of that provided on the SVD rifle; it has a rubber shoulder pad and can be removed when the rifle is dismantled for compact storage. The forward handguard is made from a high-impact polymer and fired semi-automatically. Should the operational need arise, the weapon can be used in fully automatic mode using either its original 10-round magazine or the 20-round magazines from the AS rifle.

It uses a subsonic 9×39 mm SP-5 cartridge to avoid a sonic boom. The bullet of this cartridge weighs about twice as much as that of the 9×19mm Parabellum, giving it a muzzle energy about twice as high as that of a subsonic 9×19mm Parabellum bullet fired from e.g. a HK MP5SD.

Additionally, the bullet is very effective at penetrating body armor. It is equipped with a hardened steel or tungsten tip and can penetrate a 6 mm (0.2 in) high-density steel plate at 100 m; a 2 mm (0.08 in) steel plate or a standard army helmet can be fully penetrated at 500 m; however, the rifle is typically employed under 400 m.