SVD
The ShAK-12 features a bullpup layout, with a stamped steel receiver and a polymer housing/stock. It utilizes a short recoil operating system, which means that after it fires the round the barrel slides backwards with the bolt for a short distance, utilizing the recoil of the cartridge, while the bolt keeps traveling backwards fully to eject the spent shell casing without redirecting gasses. It is unknown what kind of locking system it uses, however it most likely uses a 2 or 3 lug rotating bolt. Firing controls include two separate levers; a fire mode selector (Semi/Auto) at the rear and an ambidextrous safety (Safe/Fire) above the pistol grip. There are several configurations of the basic rifle. The first one features an integral carrying handle with a built-in rear diopter sight and a folding front sight. A length of Picatinny rail is installed on the carrying handle to accept various optical sights. Another version that was observed on some photos features a "flat top" configuration with a Picatinny rail running on top of the receiver, as well as front and rear sights installed on folding bases. Other variations have a Picatinny rail below the fore end or a 40mm underbarrel grenade launcher. Muzzle devices include a muzzle brake or a quickly-detachable suppressor. The Russian Federal Security Service has adopted the ShAK-12 in small numbers, with other designs such as the Dragunov sniper rifle and Heckler &amp; Koch MR308 remaining more common.