OTS-38 Silent Revolver

It has a captive piston cartridge. The bullet is on a piston, deep seated in the long case. The powder burns, the gas pushes the piston carrying the bullet down the long case, the piston slams to a stop in the case neck, and the bullet keeps going. The powder gas is confined in the case behind the piston. No doubt it soon bleeds down, but not suddenly with a Bang.

Pictures at
http://pookieweb.dyndns.org:61129/cartridges/SP4/sp-4.htm

There is an automatic, too:
http://en.wikipedia.org/wiki/7.62x42mm#Cartridge

A 154 gr bullet at 656 fps is not a powerhouse, the design does not have room for a lot of powder or acceleration space.

The US had a similar type built on a Model 29 S&W frame.
http://world.guns.ru/handguns/double-action-revolvers/usa/qspr-silent-revolver-e.html
Tungsten buckshot instead of a single bullet. Ouch.
 
The theory is that the bullet is not propelled by the powder charge. There is a piston inside the cartridge that is driven forward by the powder and that "knocks" the bullet out of the barrel. The piston then seals the mouth of the case to prevent escape of the powder gasses. Think about the tappet gas system of the M1 Carbine, which imparts energy to the operating slide.

Notice the range is only about 50 meters about 55 yards.

What happens to the pressure built up inside the cartridge case? I don't know.

Bob Wright
 
By reading the wiki it appears to be a gas gun. The ammo case has a piston that launches the bullet. Since there is no explosion there is no loud report. It seems to be gas powered. A subsonic bullet would have to supersonic crack. Essentially silent.
A range of 150 feet says a bunch about its power or lack thereof.
 
Yep. I tried posting that from my cell phone and it got tied up somewhere along the way. Don't know why my posting was so long behind yours. The topic had just popped up.

Oh well, no harm done.
 
I am a bit surprised that they get 650 fps that way; that is about in the same range as the .38 S&W or the old .380 British; not a powerhouse, but nothing to stand in front of, either. I wonder if the barrel is rifled or if they use a skirt, as I think forcing the bullet into the rifling would reduce velocity significantly. (The power is there initially, but unlike progressive burning powder in a conventional system there is no pressure at all beyond the initial blow from the piston.)

Jim
 
It seems to be the same principal as the ' Tunnel Gun" Tested in Viet Nam. It was a revolver with long cylinders. The cartridge used a captive piston that did not allow the gases to escape. It was designed as a weapon to be used by those deranged individuals who volunteered to enter and recon the Viet Cong tunnels. A 45 or even a .38 would do bad things to the ears in such a close confined area, Short range but effectively noiseless . One of the many devices dreamed up that were never put into wide production. It has been a long time since I read the specs but it seems that the captive piston completely sealed the cartridge when fired, no gases were allowed to escape. I know the Russians copied the principal.
 
Last edited:
You must log in or register to reply here.
Back
Top