The Swiss were the first country to adopt a self-loading service pistol; the Luger in 1900. They would keep those in service clear through World War 2, at which point they began seriously looking for a more economical and more modern replacement. During the 1940s, a number of experimental designs were developed at the SIG and W+F Bern factories in hopes of becoming the new Swiss service sidearm.
This example is a P47, one of 10 guns made in 1947, at the end of W+F Bern’s developmental series. While the preceding guns had been largely based on the Browning High Power, the P47 was a gas-delayed blowback action similar to the H&K P7, Norinco 77B, and Walther CCP (although predating all of those). Its barrel had gas ports just in front of the chamber which led into a gas piston that acted to hold the slide in battery when pressurized. Thus the slide was delayed from opening until the bullet has left the muzzle and gas pressure had dropped enough for the recoil spring alone to safely control the opening of the action.
Unlike Bern’s previous experimental pistols, these 10 P47s were all identical (and have serial numbers in the low/mid 40s to low/mid 50s). I had a chance to shoot one of these (serial number 46), and it was a pleasant enough piece, although in my experience the gas delay system did not provide a substantial improvement over what was ultimately adopted by Switzerland, the SIG P210.
I suspect that this would require the barrel and slide to be forged and machined from stainless steel. Because the P47 is a gas-delay blow-back, it stands to reason that the recoil spring must be quite stiff, even with the gas-delay. Was the P47 rather heavy for its size, Ian?
Diving into the firearm history, needs counter resets about which being the first in related field. Bern P47 seems the very first in the gas brake system used in handgun sized firearms. However, with all exiting samples, this construction should be accepted as a bolt speed slower in alongside its full backward travel rather than delaying the breechbolt opening within the very limited rearward distance in which the highest pressure in the chamber occurs. Trigger Lockwork seems interesting which a single main spring powers both sear with disconnector and hammer. Two stage trigger release looks also outstanding. A pistol made through the approach of fine Swiss watch craftsmanship.
It’s the inertia of the slide that keeps the case from backing out of the chamber fast enough to burst.
The gas pressure doesn’t get into the gas system fast enough to have a delaying effect.
The spring and gas piston serve to slow and buffer the slide later in its travel, cushioning it’s impact on the receiver, and avoiding the need for a brutally heavy recoil spring to slow the later part of the slide’s rearward travel.
I’m not sure if I totally agree. It seems to me that given a sufficiently large gas port and a piston larger than the bore diameter, that you could actually drive the slide forward.
Even in the closest gas out holes near the chamber, like P7, system works near its limits as a shock absorber and bigger calibers over 9x19mm, pressure handled within the short barrel length, gives no ability to slow the full backward bolt travel. As a result of this happening, some HK P7 pistols of bigger caliber, had to be built with needed free blowback mass discarding the gas brake tube.
Thanks, a fascinating topic with a lot going on in a simple mechanism.
“Luger in 1900. They would keep those in service clear through World War 2, at which point they began seriously looking for a more economical and more modern replacement. During the 1940s, a number of experimental designs were developed at the SIG and W+F Bern factories in hopes of becoming the new Swiss service sidearm.”
Were Swiss firms experimenting with automatic pistols designs earlier, say for export purposes?
As you know Daweo, we in west think that all in pistols is done and finished. Not so much Russians designers, they just keep designing new ones all the time. Or am I wrong? I believe they have replacement for pistol Serdyukova in inventory already and new ones keep coming. No c/s plastic, all in solid steel. How about Strizh, was it implemented?
“new ones all the time”
I assume you are thinking about ОЦ-122 automatic pistol, designed from start to be suppressed: https://topwar.ru/117920-perspektivnyy-pistolet-oc-122.html
this weapon use .45 Auto cartridge and it is (naturally) sub-sonic.
3D printing was used for creating mock-ups, mainly for testing ergonomics.
For production traditional method will be used, with 3D printing for some parts. No official data (like weight, capacity and similar) were published but published drawings give some information.
Automatic pistol might be equipped with suppressor and flashlight or similar device (see 1st photo from top). Suppressor is of peculiar form, probably to make it shorter than normal suppressor.
I have seen OC-122 somewhere, but to track current Russian pistol developments is not easy task. One of interest is this one, which discards all mechanical locking altogether (relevant in comparison to feature article) http://modernfirearms.net/handguns/hg/rus/sr1pm-e.html
And then of course Lebedev’s pistol as much as Strizh; all avantguard designs. Thus it does not look that pistol development ended up with ubiquitous tilting barrel lockup. There is more to come.
“replacement for pistol Serdyukova in inventory”
СР1 got upgraded versions – СР1М (has bigger grip safety, different sights and close automatically after inserting magazine) and СР1МП (with ability to use Picatinny equipment and suppressor), photo of second:
This is the one I like, specifically for its linear barrel travel – suited to greater accuracy. It utilises re-vitalised tilt-lock link reminiscent of Beretta M92.
Same as this: http://modernfirearms.net/handguns/hg/rus/serdyukov-sps-cp1-gyurza-e.html
I’ve gotten momentarily swayed by difference in cyrillic and latin readings. Yes, same thing. What is worth of noting is how the merged plastic handle into metallic frame; great job.
“I’ve gotten momentarily swayed by difference in cyrillic and latin readings”
There are data automatic pistols of Russian manufacture in table form:
I hope it would clear designation
“What is worth of noting is how the merged plastic handle into metallic frame;”
Then you might found MP-444 «Багира» interesting*:
it is polymer-steel design firing either 9×19 or 9×18 cartridge (capacity: 10 and 15)
* as side note: MP in MP-444 is Latin and stands for Mechanical Plant, for Russian weapon designated MP-… it mean Izhevsk Mechanical Plant
“new ones all the time”
Or you are thinking about ПСС-2 silent automatic pistol:
which use own СП-16 cartridges, with bullet of peculiar shape (see 3rd photo from top) which is designed to be sub-sonic but also able to penetrate personal armor and is said to be able penetrate class 2 (GOST)* body armor at 25 meters, and be effective up to 50 m against unarmored targets.
* – which is defined as being able to stop 7,62-mm Пст steel-core bullet (57-Н-134С cartridge) from TT automatic pistol at distance of 5 m.
This is something where western designs do not come even close. It gives tool to specialists to do the job from up-close, role in which pistols shine at its best.
It was not adopted and rather would not be adopted.
Speaking of cool, it may be in jargon of our days, but I am sure the pistol’s thermal state was just the opposite – very hot, very quick. Are there challenges in this design part of heat? You bet. One is alignment of that little ‘piston’ with corresponding bore. Besides, it surprises me it does not contain usual semi-labyrinth.
Well, all ideas on hand were tried and winner is Petter/ SIG.
“Speaking of cool, it may be in jargon of our days, but I am sure the pistol’s thermal state was just the opposite – very hot, very quick”
Is heating up of automatic pistol really that problem? How many magazines was one user supposed to carry?
Hk p7 gets hot very quickly,
So quickly that the makers added some plastic insulation to make it more comfortable for the firer’s trigger finger.
I don’t know whether anyone has managed to fire sufficient shots through the little jelly bean shaped vektor pistol to see whether it gets hot 😉
Most successfull gas brake pistol seems Steyr GB since constructed what it should be. However, new CCP of Walther, at least using the concept, looks in a par with Steyr.
I’d agree with that Steyr GB, I like it too, specifically for use of precision casting. But as we know, it did not last long even in country of its origin. So we can guess on utility of gas-brake concept; not very good one, overall.
In fact, Steyr GB seems one of the most sturdy service pistols ever produced but lost its advantages in favour of another Austian pistol which got introduced within the same time. It’s frame was made two halves of stamped steel plate and welded together. The trigger guard which made of plastic, inserted thereafter over the textured paint. Its construction seems rather cost saving but can not match with its plastic framed rival. For the time being, Umarex (Walther), seems the survivor of the system in pocket pistol genre and looks highly succesfull. IMHO.
Superb site you have here but I was wondering if you knew of any community forums that cover the same topics discussed
here? I’d really love to be a part of online community where I can get opinions from other experienced people that share
the same interest. If you have any recommendations, please
let me know. Kudos!
There are too many forums online to mention that cover this area. Due to the few enthusiastic regular commentors, this turned out forum-like