Beretta AR-70

After failing to acquire a license to produce the M16 rifle, Beretta worked with SIG from 1963 through 1968 to develop 5.56mm infantry rifles. When the companies parted ways, SIG went on to produce the SIG-540 and Beretta developed the AR-70. It was introduced on the market in 1972, and was adopted by the militaries of Jordan and Malaysia, as well as Italian special forces units (the Italian Army at large would adopt the 70/90 version in 1990).

The AR-70 takes several cues from the AK series of rifles, including the rock-in magazine with large rear paddle release and a two lug rotating bolt. In a somewhat unorthodox choice, the rifle uses a coil spring in tension for its mainspring, located around the gas piston and in front of the bolt. While this would likely cause heat-related problems in a light machine gun, it appears to have been acceptable in a rifle, as the improved 70/90 version maintain the same system. It does also allow simple use of folding or collapsing stocks, as there are no working parts in the stock.

Only a relatively small number of commercial AR70/223 rifles came into the United States in the 1980s, and they are a relatively unknown member of the black rifle family.


  1. Argentina is in talks with Beretta to manufacture the AR-70 locally. There’s already an agreement in place to manufacture the Beretta Storm pistol, which is already in use by the Buenos Aires Police Dept.

    • Thanks for the information. Sounds a bit weird, unless the rifle being considered is a much modernised version of the 70/90 model. There are literally a lot of later – and superior to the AR-70 – rifles available for purchase (including a production licence, I guess) that could warrant the attention of the Argentine military instead of this one… On the other hand, the Beretta Px4 Storm is a fully modern design and it makes sense to have it manufactured locally.

      • I’m probably wrong about the model. I do know it’s a Beretta rifle of current design and manufacture. The intention is to begin by assembling Italian parts and slowly integrate local parts. The same deal they had with the FAL.

        • Oh, sorry for my rush reply. That way, it makes much more sense! It that case, the rifle in question must be the ARX160, a modern, modular design currently made by Beretta (since 2008). The Italian army is also evaluating a battle rifle derivative in 7.62x51mm NATO.
          If the plan succeeds, Argentina will be the first country to manufacture the ARX160 besides Italy. Interesting: thanks for sharing.

          • Yes, the rifle in question for Argentina is the ARX160 7.62x51mm. It does not have the detachable barrel of the 5.56mm ARX rifles.

          • Dave, thanks for the clarification. It is interesting to hear that the Argentinean military is considering the 7.62x51mm battle rifle version, but given the long experience with the FAL, it is quite understandable.

    • I recall reading it too, however the rifle might be the following model – ARX100. Argentinians were toying with different ideas such as AUG and M16 but allegiance to Berreta won. No wonder if deal is including pistols and of pretty solid design too.

      • You are right, that’s the model designation. There’s no allegiance to Beretta. Other than the rather recent purchase of Storm pistols for the police and a few Mod 92’s for the Border Guard the last Beretta guns that were issued were the Moschetto 1938. In the 80’s Fabricaciones Militares designed a 5.56 rifle that was tested by the military and approved in principle. Economic considerations put an end to that project

        • You probably meant FARA. It was good blend of previous designs (FAL) with some indigenous ideas. One thing is certain: Argentina will be equipped with modern small arms for foreseeable future.

          Quite frankly, they surprised me with order of full size Beretta Storm pistols for police; they used to carry Bersa Thunder 380/9

          • The main armament of the Federal Police and the rest of the Provincial Police Depts. has been the Browning Hi-Power in 9mm. These guns were issued in the 60’s. Before that the Colt .45 ACP and Ballester Molina were issued. Bersa has begun to supply Thunder pistols in 9mm, mainly to the Province of Buenos Aires Police (different institution from the Buenos Aires City Police). .380 guns were never issued either to the military or police depts.
            Back in the 30’s a few Berettas were issued to Officers (not to NCOS or agents) they were in 9mm Glisenti. Ammo was nearly impossible to obtain so they used Army issue 9mm meant for submachine guns. They quickly gave up the ghost.

  2. I had read (I can’t recall who wrote it) that the main reason the Italian military were not interested in the original version of this rifle was that the stamped sheet metal was too flimsy to withstand repeated automatic fire. This is not an issue in a semi-automatic like the one in the video, but the 70/90 apparently fixed the problem for the military version.

  3. Overall, it seems to be a cross between the AK and the Armalite AR-18. I’ve heard it said that a lot of it was “borrowed” from the Stoner 63, but I don’t see that much resemblance.



    • Btw, I feel we discussed some time back the process relating to implementation of AR 70/90 into Italian military. There were at least three other Italian companies in competition and one (cannot recall name right now) was looking more advanced than Beretta. Probably in and elsewhere will be mention of it.

      • The other contenders were:
        Franchi G41, a licenced copy of the H&K G41.
        Bernardelli VB-SR, a licenced copy of the IMI Galil.
        SOCIMI AR871, basically an AR15 with a AK47 style gas piston and a lateral, reciprocating, bolt handle.

  4. Now, this is my kind of rifle. Speaking from manufacturing engineering point of view, you cannot make it much smarter; not fancy, but practical. Also, in comparison with over-built SIG550 this must have cost just half of SIG cost to make. As far as I am aware, there was heavy barreled version intended as support weapon/ LMG and thus heat generation must have been examined to necessary length.

    And yes, this is kind of ‘golden era’ rifle slowly being replaced by ARX100. Not forgotten, but kind of obsolescent.

  5. That method of disassembly- The bolt from the “spring etc” could facilitate, that… Which, could be facilitated, by the FN1900 pistol design I.e. You could have a much stronger spring than you could otherwise pull back, type thing… Theoretical, equivalent. Like. If such a cocking method was, ever envisaged etc.

    I mean you could disengage the spring, essentially to cock it, then re-engage it, without trying to pull it back- Bolt being cycled all the same.

    Just a design thought, generally. As remembered point from said pistol- At the time.

    • Er… Essentially said spring could be air rifle sized- Which you’d be hard pressed to pull back via the usual arrangement. But with this method, you could disengage, re-engage it, cycling the bolt in-between, just saying it’s a option, if anyone is thinking of using a strong spring for some reason- API or whatever.

      • The Langenhan FL pistol in 9 x 19mm used that trick during WW1. The problem with it, even in a pistol, is that with wear the disconnect between breechblock and recoil spring can become loose enough to disconnect itself during firing, resulting in the breechblock trying to Rossify your nose.

        I’d expect worse results with a rifle. Like a blown case when the breechblock opened too quickly, a case head separation, or similar displays of hot brass fragments and hotter gas emissions coming out the ejection port.

        Not something a southpaw would want to get involved with, speaking as one myself. The Ruger Mini-14 was bad enough. Never fire it left-handed unless you like hot brass up your nose or down your shirt collar.

        Kind of a shame, really, other than that I liked the little rifle. Definitely an improvement over the M16A1, even if it wasn’t the AC-556 version.



        • “disconnect itself during firing”
          So such design to be safe would need positive “out-of-spring” safety, which would prevent firing if spring not engaged (like “out-of-battery” safety prevent firing if action not fully closed)

        • If the op-rod went by the side of or passed through the bolt carrier when it was disconnected, then the bolt wouldn’t open. Durability might be an issue.

          IIRC, not entirely relevant, but consider the G41(M) contrivance, or the Mondragon.

        • Sort that with a mechanism… What is it we are trying to achieve, I.e. A stronger spring, being utilized, than you would otherwise be able to pull back. Facilitating normal functioning.

          So what’s the function, he he.

          • “I’ll start, API, with conventional bottle necked cartridges. Schell!”
            About what weapon you are thinking? If it is vessel-mounted or aeroplane-mounted or vehicle-mounted, maybe cycling might be done via pneumatic or another device?

          • Don’t know… Hmmm, I know.


            Mainly about a combination of all these “Fantastical” Russian guns you kindly show us…

            Still thinking…


            Get there eventually.

          • Is Пиропатрон used in aircraft guns, incase of failure because the pilot can’t reach the gun. If so I’ve heard of that, very good well done.


            Are you suggesting Пиропатрон in the sense of a gun powering a gun, gast gun like… Or bolt locking mechanism, or none of the above.

            Shouldn’t have searched for Madonnas pointy tits, can’t focus.

          • Oh, I had heard of a Russian aircraft gun that incase of misfire another “gun” fires into the original round. Is there another that recocks it then, or was that initial information incorrect and it was the recocking thing.

            Anyway that is not what I mean, pointy tits aside.

            What I mean is…

            A Cz29… Which…

            “This is going to go on awhile now”

          • Czech gun side locking, Cz29 is erroneous nomenclature… Madonnas tits. So that gun, which you know.

          • Right so this Berettas spring arrangement, Zh29 rifle bolt…

            The bolt… Disconnects from the main spring when it…

            I need to draw a bit, he he.

          • Ok… Basically, there’s a pivoting plate on the left side of the bolt. The front of said plate engages the notch in the Berettas spring guide thing via a protruding pin.

            The pivoting notion is pivotal.

            The receiver… Right so, the point is. Is… The bolts pivoting thing pivots away from the recoil spring thing, upon firing. It’s initially attached.


          • “Oh, I had heard of a Russian aircraft gun that incase of misfire another “gun” fires into the original round. Is there another that recocks it then, or was that initial information incorrect and it was the recocking thing.”
            Most aviation autocannons, in which Пиропатрон is used, it is fired when autocannon fail to cycle (jam) – power of powder gases is used to reload. Example is ГШ-23.
            In Р-23 by Рихтер such solution is impossible, due to peculiarity of its construction – here Пиропатрон, if fired will generate jet of hot gases “aimed” into wall of “proper” cartridge and pierce it and activate powder charge of said cartridge.

      • “anyone is thinking of using a strong spring”
        Then might use mechanical advantage like in Jo-Lo-Ar automatic pistol, namely by usage of palanca. This allow usage of strong cartridge (like 9×23 Largo).

  6. Greetings from Italy.
    The AR70 and its variants debuted in combat in small numbers, mostly in the hands of elite regiments or special forces, in Lebanon in 1982 with the deployment of the Italian peacekeeping contingent. The need of 5.56 weapons was so relevant that even the guns it was trialed against (Franchi, Socimi…) got sent over, along with acquisitions/lending from allied forces in the country (M16s). Since grunts are grunts in any army in the world, there were both subjective complaints against the perceived lack of penetration from the “new” caliber (legend says the BM59 could stop bomb cars and trucks before they could reach checkpoints, while the AR/SC could not), and objective ones against the poor plastic furniture, excessive weight/poor balance for the caliber, wear/heating of the recoil spring (a problem which has never been solved). On the other hand, it was praised for its accuracy and controllability (it’s common even in civilian models to shoot around 1.5 up to 300m with quality factory ammo).
    During operation Vespri Siciliani ten years later ( ), the enduring myth about the lack of penetration power prompted the prevalence of BM59s and other 7.62 guns among the troops, as it was expected to stop armored cars or heavy trucks at checkpoints.
    Nowadays AR70/90 variants (both long and short barreled) with folding stocks (fixed ones are very rare) and red dots/optics are (unfortunately) a common sight in the hands of soldiers or carabinieris patrolling the streets or securing sensible locations.
    With the introduction of the ARX rifles, and BM59s stricken out, ranks are of course shunning the new rifle as a lightweight plastic toy, and reevaluating the Ars…it seems short memory is a common denominator among armies anytime, anywhere!
    On the civilian market the AR70 in its original pre-90 iteration was almost exclusively sold in .222 Remington (as .223 was considered a forbidden military chambering) as the Sport Model with 10 round magazines; the AR70/90 was commercialized almost exclusively in .223 (as it had become legal meanwhile).
    Any civilian model is not particularly common nowadays (it’s comparable in numbers to the BM62), but both risk being more common semiauto rifles, derived from the ones issued by the Italian military, available on the market thanks to the latest EU gun laws preventing the sales of demilled ones (such as the BM59s).

    AR70/.223 manual:
    AR70 and other guns it trialed against:
    AR70 review at its debut:
    AR70 in Lebanon and other photos from that peacekeeping operation, from Facebook:

  7. About the recoil spring?

    What was it made from?

    Music wire, which is the usual material for coil springs (approx 1% plainish carbon steel, cold drawn into wire and cold wound into springs) has some amazing properties, like in smaller springs, a safe working loading of 125,000 PSI!
    Music wire springs begin to seriously lose stiffness at a little over the boiling point of water. The loss isn’t permanent at such low temps, they get it back​when they cool.

    Hard drawn and cold wound austenitic stainless (3 series, so typically 18-8 composition) is about 50% denser than music wire, it’s less stiff and has lower safe peak loading (so a spring made from it will, everything else being equal, be extremely approx 1 3/4 times as heavy as a music wire spring)
    But the stainless keeps it’s stiffness up to IIRC, 150°c or more.

    200°c is the chamber temperature where cookoffs start to happen quickly, so you’d hope that the recoil spring would stay well below that temperature.

    • Is that the spring used in a Mg42, I seem to remember that… Or some other German WW2 gun had a great spring. Your awfully knowledgeable about springs and things how did you, arrive at this situation, out of interest? Is it via an engineering qualification of some sort, or?

      • I don’t have one. I am just interested into how, you know all this technical stuff. I’m sure you do, but what do you do, if you don’t?

        • I read this stuff but I just don’t get it. E= Mc2 or whatever, it means nothing to me. I have looked into it, but it just isn’t working.

          What is it about, in laymans terms, what is the point of it? Knowing that might help, it’s all Greek to me- Do you have to learn Greek, so to speak. Yes? What’s ein Grosse Bier Bitte, there must be a key that enables you to buy beer.

          • If you have a college near by, lots of mechanical engineering text books cover spring calcs and design.

            If you want your own ref to read, this will keep you right,
            it covers music wire, austenitic stainless, phosphorus bronze, and things like leaf springs. And how to make your own springs. It doesn’t cover braided wire springs though.

            There’s absolutely no mention of guns in it,

            which doesn’t actually matter, because the laws of physics are universal and apply equally to all matter – regardless of what politicians and bureautwats might try to claim. (King Canute tried to show that a thousand years ago – unfortunately the message still hasn’t got through to most state adminispheres – either that or the form wasn’t filled in correctly and submitted with the correct payment).

            PS, one student house I moved into, had a clean copy of the Playboy with the Madonna pictures in it. I can’t remember whether one of my housemates wanted it, or what happened to it… I never found her attractive.
            The second ex mister Madonna, and his son are allegedly both absolutely smitten with game shooting, again Allegedly, much to her disapproval.

          • What would you be trying to achieve by having a heavy spring?

            Breech opening time in blow back is achieved by inertia, not by spring pressure.

            All that the spring does is to decelerate the bolt, and return it forward.

            If you want to stop a recoiling bolt in a short distance, use some sort of buffer,. Buffers generally absorb kinetic energy and dissipate it as heat

            The supposed gas “delay” of a steyr GB, is more correctly gas break and gas buffering of the slide.

            You can mess with spring rates and buffers, but remember that momentum is conserved, anything you do with springs and buffers, isn’t going to stop the momentum from going to the firer’s shoulder,

            The best that springs​ and buffers will do is to spread the bumps and thumps out over a longer period of time.

          • “All that the spring does is to decelerate the bolt, and return it forward.”
            According to
            In many descriptions of blowback actions, it is strongly implied that the driving spring contributes a substantial portion of the resistance which limits acceleration imparted to the bolt by the powder gases. Actually, this is not so.

          • A strong spring could work in conjunction with, something else… Swarzlose mechanism.

            Api- The stronger, the force acting forward, is surly that which will need to be countered rearwards.

          • “Swarzlose”
            Andreas Wilhelm Schwarzlose (unless you intentionally mistyped it, because to disdain toward his designs)

          • Schwarzelose’ toggle is delayed by having to accelerate the toggle linkage,

            All that the spring does, (and in the pistol iteration, it’s a torsion spring, more like something that belongs on a washing line) is to slow that toggle down a bit before it hits the stop at full extension, then close it again with enough force to feed the next round.

            Do you remember the children’s​ spring toy, the “slinky”?

            It was a big soft coil spring, that would “walk” down stairs.

            If you held the top of one, you could have about five or six feet of coils suspended and open.

            Bouncing the top up and down, you could watch compressive waves run up and down the suspended length.

            When a more normal strength spring is loaded very rapidly, that’s what happens

            The first coil or two compress, and that compression runs off down the spring as a wave.

            There’s actually very little resistance to movement there.

            With inertia, especially if there’s some accelerator mechanism in there, like levers, toggles, roller delay etc
            You can have quite a lot of resistance to rapid movement.

            If you want to try API with conventional bottleneck rifle cases and loads,

            There might be slight advantage in having a very fast moving breech bolt, so that firing can take place with very little case movement

            But expect a hideously fast rate of fire, and a lot of battering of the sear.

            An alternative would be to use several very narrow extractors, and have matching slots cut in the back of the chamber,

            The idea of the narrow slots is so the case side walls will bridge the slots without​ popping.

            Youll also need lots of fluting in the chamber to reduce the stress acting normal to the case and chamber contact

            Either flutes or grease, they both do the same thing.

            You might also need to use steel cases.

            The 7.62×39 might be a better choice than the NATO rounds, as the NATO stuff s loaded to over 50% higher pressures.

            Even that varies ridiculously between NATO members, for example British stuff is even more ridiculously high pressure than united state stuff, and will bugger up M4 carbines in a very short time.

          • Forgot to say, ak mags are more durable and less prone to malfunction than stanag mags.

          • Is there difference between braided-wire spring and stranded-wire spring or these names are equivalent?

          • Braided wire springs have several strands of wire twisted together, it looks like the coil has been made from wire rope.

            The advantage of winding a spring from a braid rather than a single strand, is that you can arrange the braid so that it tightens as the spring is loaded.

            That way, if the spring is in a situation where it gets very fast loading, like the gas rod spring in the AR70 will,. The tendency for a wave of compression to run back and forth along the spring, is opposed by the braid tightening.

            It turns out that the high frequency compressive waves running back and forward in a coil spring, give an increased number of cycles of compression and relaxation, on top of just the single compression and relaxation from firing a round. Those additional cycles of loading and unloading contribute towards​ metal fatigue,

            Forming the coil from a braid, dampens those waves, and significantly adds to the service life of the spring.

            It is of course possible to design springs which will sustain a given duty, without ever suffering from metal fatigue… The valve springs in poppet valve internal combustion engines are an example, the number of stress reversals which would result in a fatigue failure is exceeded with only a few hours of running an internal combustion engine.

            However, a military rifle is built for a finite life, say 20k rounds as absolute Max, and that’s likely to include a few re-builds along the way.

            So there’s significant weight to be saved by designing for say 99% or 99.9% confidence of a service life of 20k rounds

            And using a braided wire spring, allows a given confidence limit for spring life to be achieved with slightly less weight than using a spring made from single strand of wire, allowing that saved weight to be used somewhere where it is needed more.

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