BSW Prototype Pistol

Strange Guns has finally uncovered the identity of a pistol that was for some time a mystery to that site: The BSW pistol prototype, a weapon that was a competitor to the Walther P38, and one of the few handguns with a gas system (more on that below):

As Ian notes over at, the James D. Julia Auction Company has just opened their own “research library”: a catalog of all of their auction items going back to 2002. As soon as I saw this I clicked on the link and searched for BSW… as it turns out my hunch was correct, and this little baby popped up in the results.

The firearm is a Berlin Suhler Waffenwerk (BSW) prototype gas-operated pistol from the mid-1930s. It’s a very strange gun who’s true identity I’ve been chasing after for some time. 

The general existence of this pistol has been known both on and off the internet. I first stumbled across a photo of the weapon in a very generic coffee table firearm book in around 2009, although the description provided failed to mention anything about the peculiarities of the mechanism. As I would come to find out later, the noted internet gun writer Maxim Popenker had written an article in 2005 briefly describing several gas-operated pistols and in particular one swinging gas-lever specimen manufactured by BSW, although the Russian text proved extremely difficult to translate satisfactorily and no photos were included with the description. It was around 2012 when a few small details caused me to suspect that the semi-confusing pictureless article might be describing the very same gun who’s picture, sans description, I was already familiar with.

How does the gas system work? It’s not entirely clear, but the gas impinges off a swinging lever arm (a la Colt 1895 “potato digger”), which may perform one or more functions, including unlocking the slide from the barrel. This weapon is truly bizarre; a Russian article – machine translated below – by Maxim Popenker has more information:

In the mid-thirties creation army pistol with automatic vapor took German company BSW (Berlin Suhler Waffenfabrik). Based on the design of Browning swinging gas piston, located under the barrel, engineers BSW radically reworked it, creating a curious enough sample chambered for 9×19 Parabellum. Unlike systems Browning Ehbetsa Oznobishchev and in which the piston rocked by quite a wide arc, the gun piston BSW swerved down only a slight angle. In addition, the gun did not have a single BSW shutter closes the trunk when a shot – the role of the locking member, and along with the accelerator gate himself played the gas piston. In the position before firing the gas piston head included in the aligned openings in the lower part of the casing and the shitte-rbarrel, thereby locking the the shutter is rigidly fixed relative to the barrel. Once in the moment of firing the bullet passed vents, the piston begins to move down the arc of swinging on the long arm around an axis in front of the trigger guard. In the process of their movement down the piston out of engagement with the gate, while a special bevel acting upon it, and thus, giving an additional acceleration gate. Small swing angle of the gas piston on the lever did treatment with this gun a little more comfortable and safe, but when manually operated weapon was necessary to pre-delay gas piston down before it will be possible to manually move the slide back. To this end, the piston arm in from of him had special notches, make more comfortable grip lever fingers. In addition to the original scheme of automation, gun BSW had a whole series of interesting design features, such as a frame made of duralumin – aviation aluminum alloy, as well as a hidden trigger located in the handle of the mainspring that is automatically decompressed in the formulation of arms lock (trigger while remained cocked). No one know what it did not like the gun of the military department Wehrmacht, but the fact remains – the replacement of the famous Pistole 08, better known as <<Parabellum>>, gun company BSW did not become.

The translation is too poor to tell precisely how the gun worked, but it seems clear that to work the slide manually, one had to pull down the gas delaying lever – a poor characteristic for a service pistol. It also mentions that the frame of the pistol was made of aluminum, making the BSW prototype one of the first firearms with this feature.

Nathaniel F

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He is also the author of the original web serial Heartblood, which is being updated and edited regularly. He can be reached via email at


  • echelon

    I could be wrong but that trigger looks like it would have an extremely long pull to it.

    • Tom

      Since its most certainly a single action i would guess the trigger is “set” by cocking. Looking at it I doubt you get a finger in the trigger guard (especially with gloves on) so it would serve as a sort of reminder that the weapon was not cocked.

      • echelon

        It’s possible but since I don’t see any exposed hammer or obvious safety mechanism for a “cocked and locked” setup I wouldn’t assume it’s a single action gun.

        • Tom

          True but cocked and locked was not considered that necessary or safe back then – I think somtimes we forget just how ahead of its time the 1911 was – so lots of pistols were meant to be carried with a magazine in but nothing under the hammer – like the TT33. Also it would make sense that and safety would be on the left side – ambidextrous controls were a long way off. Of course all this is just speculation on my part. If only we could get our hands on it.

          • Sulaco

            Actually the “ahead of its time” 1911 was built at Army request with the grip and slid safety with horse mounted cavalry in mind. The
            Army manuals of the day insist the slid safety be actuated upon finishing firing the pistol so that it would be “safe” until the horseman could dismount and clear the pistol. Actually carrying it cocked and locked was in violation of regs…

          • echelon

            Yes that could be the case.

            My southpaw bias was coming through on the safety thing! 😉 Of course the safety would probably be on the other side…

            An interesting piece for sure. I’d like to see slow motion video of it being fired.

      • noob

        yeah, I didn’t understand the bit about the internal, hidden trigger.

  • Joe

    I will get on translating that for you all. It’s pretty clearly written.

  • The Colt “Potato Digger” of 1895 worked in a similar way to this (jury’s still out on whether it was the same way or not).

    Keep in mind there’s a swing-arm that comes down, so it probably is not the greatest match for rifles, as that would be happening right where your hand would want to be.

  • Ian McCollum

    I happen to know the current owner of this piece, and will be doing some high-speed video of it shooting. 🙂

  • Thanks, Max!

  • Tom

    I should have read the link 🙂