Tribuzio Ring-Trigger Squeeze Pistol

Lot 1235 in the September 2020 RIA Premier auction.

This palm-squeezer type pistol was designed by Catello Tribuzio (sometimes spelled Trabuzio) of Turin around 1890. It is a very simple design, including a clever dual purpose ejector that also acts as the sear for firing. This example has a 7.65mm bore, although sometimes these are described as 8mm – whether there were two versions or simply a repeated error in documentation (since there is no ammunition available and I doubt one of these has actually been fired in at least 50 years) is not clear.


    • Looks to me as though palm pressure locks the breech, as with this ammo you would not have a lot of recoil to fight against.

      • “palm pressure locks the breech”(C)
        And there is.
        This pistol is featured in the British TV series The guns.
        But there are no cartridges for him either.

          • Thanks.
            It seems that is simply the inclination of the surfaces between the lever and the bolt that locks it. When the bolt is pushed rearward by the recoul, it can only push the lever downward, where there is no freedom of movement, so the bolt is fully locked. That’s why you can see the lever to move some mm rearward before engaging the bolt when Ian releases the trigger. That movement is needed for the lever to cease to be the lock itself.
            It’s a pretty clever design and, since the lever seems quite sturdy, there is practically no limit to the power of the cartridge it can locks, as long as the frame is strong enough.

    • Gun seems working in a way similar to “Remington Rolling Block” system… Bolt works through linear and lever works circular, if bolt and lever connection is made like integral, bolt needs more space upwards to move which seems absent and keeps its place… An ingenious work… IMHO.

      • Sounds kind of like the Spencer, where there’s a subtle drop at the beginning of the roll to permit unlocking with one more-or-less fluid motion.

        • Spencer’s bolt works in falling block principle as being at upright angle to the bore… Its release mechanism works on toggle lock system and needs an initial motion to free the mechanism. Whereas this gun’s bolt works on the same axis with the barrel. It seems no need for an initial freeing motion for the lever. The seen play at lever working axis in Ian’s video, should be come from the lack of support for lever axis screw right tip which located at the side plate which taken out for demonstration… IMHO…

  1. Maybe yes.
    Foldable trigger.
    A transverse plunger on the trigger rod simply holds it in the extended position.
    The bolt is locked due to the “dead center” on the upper beveled surface of the lever.

  2. Does the trigger fold or hinge out of the way when the gun is in your pocket? It must take quite a squeeze to fire but still seems quite unsafe without a sheath or holster.

    • Patent writes the trigger slides in as pressing the little button at right into its tubular recess for safe carrying and pushed forward into action as the same button locking it at working position… It is not folding… The gun seems safe enough,,,

  3. If reviewed, it would be seen that this gun is so cleverly thought and designed that can be applied any of current pocket pistol caliber… IMHO…

    • To push modern rimless cartridges into battery would be surely easier.
      Making some component to pass around the magazine, you could probably build a Tribuzio capable to accept 1911 magazines.

  4. C.Tribuzio was awarded British Patent 18,097 on 10th November 1890. The patent has a drawing of the mechanism and a description of it’s operation. The cartridge in the drawing has a short dumpy rimmed case, the length being about the same as the diameter.
    The trigger is a different shape.

  5. The German patent (DE 58532) from November 8, 1890, gives the name of the inventor as Castello Tribuzio (with s) and the calibre as 8 mm.
    The Swiss patent (CH 2927) from November 10, 1890, gives the name of the inventor as Catello Tribuzio (without s), the calibre as 8 mm and the name of the pistol as “Pistola Lampo Salva Vita”.

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