1st Stop Firearms

The OTs-38 is a very specialised ‘silent’ revolver that fires the self contained 7.62x41mm SP-4 special purpose noiseless cartridge.  The revolver requires no silencer instead it relies on the internalisation of the explosion of the cartridge’s propellant. This system also has the added benefit of preventing any visible muzzle flash.

7.62x41mm SP-4 special purpose noiseless cartridge

The revolver’s ammunition, the SP-4 cartridge, was developed during the 1970s by the USSR.  It uses a unique single-stage piston propelled by the round’s explosive propellant.  Once the cartridge’s primer is struck it ignites the propellant pushing a brass driving band - or ‘piston head’ forward.  On top of the ‘piston head’ sits a cylindrical milled steel projectile which is propelled from the cartridge casing but once the driving band reaches the mouth of the casing it stops containing the sound and flash of the bullet’s internalised explosion.

Designed and developed in 2001 by konstruktorIgor Yakovlevich Stechkin at TsKIB SOO an arms manufacturer based in Tula a city, 120 miles south of Moscow, famous for its arms manufacturing.  The pistol was produced after a request from Russia’s security service, the FSB, for a quiet pistol capable of killing an enemy at 50 metres.  The pistol has a number of interesting design features, contrary to appearances the pistol’s barrel is actually aligned with the cylinder’s bottom chamber, the barrel-like tube at the top of the OTs-38 is actually an integral laser sight - the on/off switch for which can be seen on the left side of the frame (photo #1&3).  This barrel position has the added benefit of reducing the pistol’s recoil dramatically minimising muzzle rise.

While the pistol is primarily double-action it can be carried ‘cocked & locked’ to enable quick, crisp first shots.  To aid this it has ambidextrous safety catches on both sides of the frame.  Unusually the revolver’s 5-round cylinder does not swing downwards out of the frame but rather it hinges from the front of the cylinder and arcs outwards to the right (photo #2).

PSS & 7.62x41mm SP-4 ammunition

The OTs-38 was designed as an alternative to the PSS Silent Pistol, developed in 1983 by TsNIITochMash who also developed the APS underwater assault rifle.  The PSS also fires the 7.62x41mm SP-4 round but from a 6 round single-stack magazine.  While the PSS has an extra round it has the drawback of ejecting its spent casings like a conventional blowback pistols. This means the user will leave spent casings behind - not always desirable in covert uses.  Both pistols firing the SP-4 round have seen use by Russia’s Spetsnaz, MVD and FSB.

China’s Type 64 Internally Suppressed Pistol

Other Unusual Firearms

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Image One Source

Image Two & Three Source

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