Captive piston ctge

captive piston ctge from Slovac origin (I think !!!)

The bottom part of the case is in white plastic (L = 34.7 mm)
The top part of the case is in aluminium (L= 6 mm)

case diameter : 11.45 mm (plastic and aluminium)
case length : 40.7 mm

The exit hole is 6 mm but it is going decreasing.

Therefore I think the hollow point bullet has a diameter of less than 4 mm

a 357 magnum

Fascinating! I had never seen pictures of either of those rounds posted here so far. I was especially surprised at the very conventional looking .357 Magnum (other than the stem). Do you know who made them?

I wonder if the captive pistol was ever tried in a conventional auto pistol cartridge? I know that the Russian round that looks somewhat like a 7.62 x 39 case is used in a semi-auto special purpose pistol (silenced) but it is quite different from any conventional pistol cartridge in shape and size of course. I used to have a video tape from Russia on the firing of that pistol and some other of the newer Russian deisngs (well, not so new anymore, are they?). Wish I could find it. I would like to see it again. Must have given it away to someone since we don’t have a machine to play it here at our house.

At any rate - nice posting. Something really new, to me anyway.

Hi John !!

  1. Who did make the 357 Mag ??
    I would say your government.

  2. About Russian captive piston rounds I have a video (unfortunately impossible to watch again here in Europe because it was shot with an US standard (NTSC) camera).

A friend of me is shooting in a military Russian shooting range with a lot of captive piston riffles and submachine guns. But no pistol.

  1. In the US you have also a 357 Maximum necked down to 6 mm.
    It is shot in a kind of Derringer.



Hi Yuri.

If I remember well (and I told you I cannot see it again because it is US NTSC standard) some guns were silenced you are right.

But one or two at least, had none or didn’t look like.
Perhaps the silencers were integrated inside the weapon and you are right.
From the video the ctges look like AK47 rounds but different dimensions.
I will check anyway



Hi Yuri !
I found the cassette and the notes I wrotte on the back of the cassette.

I neglected to use them to writte a report when they were fresh in memory and now it makes at least 5 years ! I give them here under as they are written.

Next time I go back to the US I will play the cassette and shoot it with my mobile phone.

Some of the weapons were integrally supressed , I confirm, and I took note of a new caliber : 9x39

The weapons shot were :

FSB, Makarov, Grusin, AKM, SVD, PKM, AN-94, VSS, Vintorez

Does it talk to you ?


Jean-Pierre those you have listed do not use cartridges with the captive bolt system.

I think the “FSB” here means not a gun but the successor of the KGB and Grusin might be well Gyurza. Just a thought.

The NRS-2 Scout Knife is an interesting weapon. It consists of a conventional combat knife blade with a barrel in the handle, holding an almost totally Silent 7.62x42 SP-4 captive piston cartridge with an AP bullet. There are some photos of a few types of these Russian silent cartridges on Tony Williams’ site if I remember correctly.

Falcon, the SP-4 is no AP cartridge.

Here you can see them all: … 020ea98104

[quote=“EOD”]Jean-Pierre those you have listed do not use cartridges with the captive bolt system.

I think the “FSB” here means not a gun but the successor of the KGB and Grusin might be well Gyurza. Just a thought.[/quote]

Hi Alex!
What is the 9x39 ? regular ctge or piston captive one ?
What is Gyrza ?


The 9x39 is a regular cartridge (necked out 7.62x39) which is used in a series of small assault rifles and a sniper rifle named “VSS”.

The Gyurza is a pistol in 9x21:

There is also a SR-2 “Veresk” sub machine gun in 9x21:

The 9 x 21 must be scarce ?,
What is Vintorez ?
And AN-94 ?


The AN-94 is the successor of the AK-74 and was adopted years ago.

The “Vintorez” is the silenced VSS sniper rifle (I can’t stand it when people use nicks insetad of correct designations).

Not fitting the subject to 100% but the new service pistol of the Russian Army is the PYa.
Caliber is 9x19 but they planned also exchange barrels in 9x18 Mak. and 7.62 Tok. because of huge qty. of ammo in stock.


The 9 x 21 must be scarce ?,


Depends much on your connections. People here may tell you better than I could.

Hi Alex !
I found one, it is OK now. And a 9 x 41 also. Just waiting for them.

But all that doesn’t tell us what is this Slovac ctge?
Or if the steel one is really an US round !


[quote=“EOD”]Falcon, the SP-4 is no AP cartridge.

Here you can see them all: … 020ea98104[/quote]
Cheers EOD, I always thought the SP-4 was loaded with an AP bullet. Thanks for the link as well.


I think the steel cased round is from the USA (and probably made by AAI).

Here is a picture of one next to the .44 QSPR and then other pictures of the base and projectile - note the shear pin which must mean the projectile has a stem which extends down into the case and probably rests on the piston.