Russian PSS Silent S/A Pistol:

The PSS auto-pistol was developed in Russia around 1980 & first issued to KGB Spetsnaz in 1983 - being made in their special weapons plant at TsNIITochMash (weaponry precision engineering section)..
This semi-auto pistol is one of several Russian handguns specially produced for SILENT function in covert operations without a bulky silencer. The perceived noise level is very low & mainly caused by the mechanics - being at a similar level as a well silenced .22 rim-fire.

PSS Silent Pistol

The PSS has a magazine capacity of six rounds of the long(ish) cartridges, and uses a floating chamber - it might be described as a 'REACTION OPERATED' semi-auto .. as all propellant gases are retained inside the captive piston cartridge.  The pistols grip is deep from front to rear to take the magazine and gives the piece a chunky look.

SP4 Cartridge On The Right Has Been Fired.

The SP-4  captive piston steel copper washed cartridge is a well proven 7.62×42mm necked round - the same as used for the OTs-38 Stechkin silent revolver.

This cartridge uses a similar diameter projectile and over all size & shape to the old Nagant M1895 revolver rounds (**Interesting to recall that the very efficient Nagant Revolver was able to be effectively silenced**) ... and is also the same bullet caliber as 'thirty-two' caliber revolver rounds & .32" ACP.

Stetchkin OTS-38 Silent Revolver.
(Fires from the bottom chamber)

The SP-4 cartridge contains an internal piston and a powder charge of around 3.5 grains, with the stem of the piston inserted into the base of the bullet as an alignment  'guide'. On firing, the piston drives the steel bullet from the barrel to an effective range of 25 meters plus. On firing the internal piston seals the cartridge neck, preventing noise & blast from escaping.

The 155 grain mild-steel bullets have a muzzle velocity of 620 feet per second and muzzle energy of 133 ft,/lbs.

These various covert operations handguns all work fine and are established technology. - However they all, - PSS Pistol,- OTS-38 Revolver, - and the American QSPR Revolver, are the products of non-commercial MILITARY development & each depends on non-standard 'special' sized ammunition and 'special' expensive custom-made firearms.

US QSPR 'Tunnel Rat' Revolver

If you can think it .. you can make it. - A captive-piston version of some regular handgun cartridges could be produced commercially - if permitted .. See the Post about my "standard caliber"  Silent Handgun Cartridge Patent .. Link:

https://flicense.blogspot.co.nz/2017/02/silent-handgun-cartridges.html

- Here's further Link to an excellent full review of the PSS Pistol:

http://www.sadefensejournal.com/wp/?p=307

Marty K.

After researching & writing 1,036 blogs I've got something NEW to try .. I've signed-up to Patreon. - In over five years I've not made one cent from this .. NOW you can send me a wee support $ - starting from $1. to get all this stuff from New Zealand - over a year that's nearly the price of one Shooting magazine. - Am I worth it?


https://www.patreon.com/posts/24075745

Notes On Shooting & Hearing Loss:
Firearms Are Loud

Exposure to noise greater than 140 dB can permanently damage hearing. Almost all firearms create noise that is over the 140-dB level. A small .22-caliber rifle can produce noise around 140 dB, while big-bore rifles and pistols can produce sound over 175 dB. Firing guns in a place where sounds can reverberate, or bounce off walls and other structures, can make noises louder and increase the risk of hearing loss. Also, adding muzzle brakes or other modifications can make the firearm louder. People who do not wear hearing protection while shooting can suffer a severe hearing loss with as little as one shot, if the conditions are right. Audiologists see this often, especially during hunting season when hunters and bystanders may be exposed to rapid fire from big-bore rifles, shotguns, or pistols.

Hearing Loss Due To Firearm Noise

People who use firearms are more likely to develop hearing loss than those who do not. Firearm users tend to have high-frequency permanent hearing loss, which means that they may have trouble hearing speech sounds like "s," "th," or "v" and other high-pitched sounds. The left ear (in right-handed shooters) often suffers more damage than the right ear because it is closer to, and directly in line with, the muzzle of the firearm. Also, the right ear is partially protected by head shadow. People with high-frequency hearing loss may say that they can hear what is said but that it is not clear, and they may accuse others of mumbling. They may not get their hearing tested because they don't think they have a problem. They may also have ringing in their ears, called tinnitus. The ringing, like the hearing loss, can be permanent.

Michael Stewart, PhD, CCC-A, Professor of Audiology, Central Michigan University.