How Does it Work: Short Recoil Operation

Short recoil is the most common system used today in self-loading handguns, and it also used to be fairly popular in machine gun designs. The basic principle is that the bolt and barrel (in a handgun, slide and barrel) are locked together for an initial travel substantially less than the overall length of the cartridge. After typically a few millimeters of travel, the barrel stops and the bolt or slide is able to continue rearward to extract and eject the empty case. Short recoil can be paired with virtually any locking system, but today the Browning tilting barrel system is most common.

Short recoil has never been popular in shoulder rifle, as the reduction in mechanical accuracy from the moving barrel can be undesirable. In handguns and machine guns, this accuracy reduction is generally below the threshold of relevance.

37 Comments

    • Technically, yes, but one Regulus Pilon patented and demonstrated a self-ejecting and self-cocking system based on barrel recoil (USP 2998, 1863). Whether it was short-recoil or retarded blowback is still a subject for debate.

      Also, the Borchardt/Luger “Parabellum” toggle-lock is essentially Maxim’s turned upside down, with the toggle “breaking” upward rather than downward.

      cheers

      eon

  1. Can anyone confirm that the Peruvian “Fusil Automático Doble” is a short recoil design?
    Some resources say delayed blowback (but fail to describe how this is achieved)
    But others have said reciprocating barrel

    • There is very little info on that design. I saw a picture (bullpup configuration) with description saying it is delayed blowback operated. It was produced in very limited number of prototype(s).

      Peruvian military fielded number of different foreign made rifles. Visit to their warehouse would be an exciting event.

  2. Hate to say it, but this video could have been even clearer with a couple of Bruno’s styledb colored animations… So many interesting ways of unlocking bolt and barrel that you have shown.

  3. This video, albeit coarsely informative, is a replay of previous as I believe. It never fails to draw attention.
    As for short recoil use on rifles, I do not recall a mention they would be “less accurate”. One such example would be 1941 .30cal Johnson rifle.
    https://en.wikipedia.org/wiki/M1941_Johnson_rifle

    Was it any better than Garand M1? Probably not. One thing against is the long unsupported barrel which makes it vulnerable. But as we can see in current “6.8mm” trials, one of contenders (cannot produce the name right now) is doing just that. Let’s see if they succeed.

    • My guess the reason short recoil rifles are not popular is in the difficulty in mounting a bayonet to a recoiling barrel. While one could use a full length sleeve to mitigate this, like the one the MG42 utilizes for different reasons though, would result in a heavy firearm.

      As for the accuracy, with enough money, anything is possible, see the super expensive high end m1911s that have great accuracy, I think it is just easier to make other operating mechanisms more accurate. See the AR15/ AK debate for a similar situation. Are AKs impossible to make accurate, no, but for the same mass and money invested the AR will have a more secure sight mount with a lower recoiling mass and straighter recoil movement. With that said, honestly for most shooters, they will not notice the difference in how accurate an AK versus an AR15 is as the difference is outside what the shooters capabilities are to actually utilize. A sub MOA rifle is still a 2 MOA rifle in the hands of an okay shot….

      With the NGSW candidates I only think one utilizes short recoil, the SIG. They use recoil mechanisms in concert with a gas operated action to help mitigate recoil similar in concept to the recoiling action on an FG42 and more recently the XM806 HMG. The only true recoil operated rifle in the NGSW trails that I am aware of was the Mars version which was long recoil operated.

      • That rifle in NGSW/NGAR trials is General Dynamics candidate, as I believe. It is in bullpup configuration and it combines gas operation with recoil. Strange and apparently quite complex.

  4. “Short Recoil Operation”
    Does Mauser Selbstlader M1916 https://guns.fandom.com/wiki/Mauser_Selbstlader_M1916
    belong to this category?
    Description: rifle used a flapper-locked recoil operation. The barrel, unlike most recoil-operated weapons, does not move; instead, a cam plate situated in the rear receiver helps unlock the bolt, along with two large flapper locks.
    Is that short recoil? long recoil? other recoil?

    • It might be classified in “Inertial operation” since used the recoil of full mass of rifle to operate the unlocking
      device…Difference from current concept being that did not collect the gained momentum in an elastic media to use ıts decompression sequence but, transmitted directly to unlocking mechanism… That it used one way ticked insread of current two…

      • You might be correct. By definition a firearm is “recoil operated” if its barrel moves the necessary distance to unlock the action. Otherwise it is not.

        • As a general rule, if the barrel and breech remain locked together for a distance equal to or greater than the cartridge OAL, it is considered “long recoil”, as in shotguns like the Browning Automatic 5, and some other weapons such as the Chauchat machine rifle or the Gabbett-Fairfax “Mars” self-loading pistol.

          If the barrel and breechblock are unlocked from each other at a distance shorter than the cartridge OAL, the action is “short recoil”. The classic example being the ubiquitous Colt-Browning pistol lock or its simplified development, the Petter lock as seen on first the French MAS M1935S and today on many self-loading pistols, notably the Glock.

          Long recoil and short recoil were in competition in the early decades of automatic action development, but in the end short recoil won out on grounds of simplicity of manufacture.

          It’s not that long recoil actions can’t be reliable; the Chauchat and Mars pistol gave the concept a bad name, but no one has ever accused the Browning Auto 5 of not working correctly.

          But short recoil systems generally only require one spring to handle all the moving bits. Unless they’re two smaller springs discreetly tucked away somewhere, as on the Walther P.38. Note that the Beretta M9 is essentially a P.38 with a single Browning-type recoil spring underneath the barrel.

          cheers

          eon

    • A rotating bolt is a locking mechanism, not a method of operation. A rotating bolt can be gas operated, manually operated, delayed blowback operated…

      What is the name of the newly popular action using an unlocked bolt and a bbl that recoils a short distance with the bolt? Are we looking at short recoil blowback in KelTecs and FNs?

      • FN is “Delayed Blowback” which a slide engaged lever, with a shorter arm, forces the barrel backward in slower speed… Extraction begins but happens slower than pure blowback by means of rearward moving barrel.

        KelTec may be described as “Supposed Delayed Blowback” since there is not force for the movable barrel backward other than the over obturated shell case through friction… Over obturaion is supposed for magnum rounds only. Delay purpose is same with the FN…

  5. Applied to rifles.
    Recoil with a short barrel stroke, provides less recoil (pun intended) and dispersion than rigid barrel lock schemes.
    Reliability is usually less than with a stationary barrel, and the design itself is technologically more complex.

  6. “Short Recoil” was also used a few times at smooth bore shoulder guns… Val. Browning’s “ Double Automatic”, Armalite’s AR 17 and FN’s A500R were samples… Among them only AR 17 could be descibed as a true short recoil gun since bolt unlocking was accomplisned by very small barrel back movement… Others shared their actions with inertial operation… Besides, Huglu from Turkey made a short recoil shotgun named “ NitroBeast” a few years ago but discontiniued nowadays…

  7. Suggestion for the next one: Cook off. It comes up frequently in videos of machine gun and even regular shooters aren’t likely to know much about it due to how it only applied to machine guns.

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