A Mysterious Brazilian ArmaLite AR-18

Ronaldo came across a negative of a photo of an AR-18 he photographed at the Brazilian Army’s Fábrica de Itajubá back in October 1982. The gun is unusual for having a rifle-length handguard, carbine-length barrel and rifle-style flash suppressor. It also features a fore grip that matches the pistol grip’s design but it is not a repurposed pistol grip (it has no trigger guard cut out).

Maybe you and your readers may be interested in the enclosed (poor quality, scanned from an old negative) photo of a most unusual — at least for me – ArmaLite AR-18 rifle. It seems to be a very early production example, as reveals the small cocking handle straight to the right side, and features the standard rifle-size handguard, but its barrel is definitely shorter, maybe with the same length of the carbine barrel. The flash hider is the prong type (the carbines had a conical one). Of course, the forward support grip is well to the front of the gun.

I photographed this specimen at the Brazilian Army Fábrica de Itajubá (Itajubá Factory), now part of IMBEL, in October, 1982. I just found this single negative, and I don’t recall having talken notes of markings, much less photographing it in detail. Shame on me!

Could anyone throw some light on this curious AR-18? An/or have any reliable reference on the actual legth of the carbine versions barrels? I believe there have been three of them.

Can anyone help Ronaldo out? Has anyone seen one of these AR-18s before?

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • JoeBob

    I don’t know what it is, but that’s one sexy dissipator. I wish Armalite still made AR-180’s.

    • I agree. A modern AR-180 would be very cool.

      Then again, just about every new gun these days is a AR-18 inside.

  • denny

    Hello to Ronaldo!

    I do not have the answer, just observation: this is strangely ‘modified’ AR-18. So far positioned auxilliary grip is just plain out of place. I feel genuinly attracted to AR-18; it is a seminal and evergreen design which inspired so many people. Let’s hope someone will pick up the production again (I know there is myriad od aluminum-tubed copies; I like the steel).

  • DougE

    Someone was really ahead of the curve back then.

    • Big Daddy

      Once you start to look at pictures of what field mods where made to weapons a lot of people where ahead of the curve. I have seen a lot of field mods and certain special units make mods to weapons over the years. Years ago there was not the mid set to modify weapons like there is now and companies to sell them. So many of these great ideas disappeared.

      It was very interesting when I read about the men who killed Bonnie and Clyde. About their weapons and modifications like extended magazines. Clyde himself cut the end of the barrels off his BARs so that he could fire them out of his car easier.

      The most interesting thing I saw was a WWII video on how to shoot a Thompson SMG on youtube. If done correctly there was no muzzle rise on full auto or even flip.

      I remember seeing pictures of how to fire a M-3 grease gun and used it when I was issued the weapon. Nobody instructed me on how to fire it, I used old pictures from a book.

  • gunslinger

    i wonder if this was a “bubba”

    looks cool..

  • Ian

    The forward grip does appear to be a re-purposed pistol grip that has had the tang cut off of it.

  • I may be able to. I’m friends with the guy who bought the costa mesa armalite inventory a decade or two back and he’s almost all the original paperwork, including invoices to foreign customers. I’ll call him up today.

    • An update from my friend with the armalite inventory:
      Throughout the life of the Costa Mesa factory they would often experiment with one-off guns, including creating some of these odd vertical foregrip configs using pistol grips sans the tang. This particular one pictured was a very early model judging by the charging handle. Both Costa Mesa and Sterling made these before switching to the more common charging handle.

      Strictly from a costa mesa perspective they did make some dissipator-like ar-18s but as far as what can be derived from the documentation were not made that short.

      This is not to say it couldn’t have been made from costa mesa, the amount of experimentation and customer-specific guns that came out of there is noteworthy.

  • Cannon

    The foregrip looks similar to the ones used by the British SAS. Didn’t you post a pic recently?

    • Brandon

      Yes the AR18k. That one has the grip mounted further back, and has a trigger cutout (like a standard A2 pistol grip). The link to it is in the ‘related posts’ section of this post

      Could this be a custom one-off?

  • Pedro M

    Ronaldo Olive of “Revista Magnum” fame?
    That was a great magazine…

  • Lance

    Not surprised AR-18 poped up all over the third world in the 60-80s.

  • Mike Knox

    Users for setups like these typically detatch the stock because of the front grip’s angle..

  • Nathaniel

    I think that’s a factory AR-18 Carbine.