POTD: A Mystery Fifty Cal

Gun writer Ronaldo Olive sends us photos of a .50 cal sniper/anti-materiel rifle captured in a drug raid. He says:

This .50BMG rifle has just been seized in Rio de Janeiro by crack BOPE (Batalhão de Operações Policiais Especiais) Military Police troops in he possession of a group of drug dealers, but I have been unable to identify it for sure. The stock appears to be one marketed by ArmaLite for its AR-50. Any suggestions? Thanks.

50 Brazil 1 50 BRAZIL 2 50 BRAZIL 3

The rifle looks very similar to an Armalite AR-50, even being marked “Armalite AR-50A1” but is clearly distinct, having a magazine well, a different barrel shape and muzzle brake, different finish, different rail, and other details. A photo of an Armalite AR-50 is below, for comparison:



Can anyone identify the rifle?


EDIT: Ronaldo sent us a clearer picture of the fake markings on the rifle’s receiver:

50 bope_4

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 nathaniel.f@staff.thefirearmblog.com.


  • MR


    • MR

      Kidding, most likely homebuilt, like that Mexican Colt Commando a while back.

  • toms

    Looks like an EDM or windrunner OR possibly a knockoff PGN

    • No. No it doesn’t. Not in the slightest.
      Crack – Stop smoking it.

    • FarmerB

      Nothing like it…

  • Jordan

    Steyr HS 50 clone, perhaps. Saw several in Iraq…

    • John

      Emphasis on “clone” here.

      Since it came from Brazil, it was probably easier for cartel members to bribe select Taurus workers and make a useable rifle–but not connected to any of their products–than it was to import anything from another country. The markings might have been made to throw off the track.

  • iksnilol

    Reminds me of the Steyr HS 50. The fake markings means it is most likely a homebuilt clone.

    EDIT: It has a magwell, so it can’t really be a HS 50 now can it?

    • Wetcoaster

      HS 50 M1 has a 5 round mag, but it’s to the side and not below.

      • iksnilol

        Yeah, I forgot, they upgraded it. Though most of them are single shot from what I know.

  • Wetcoaster

    That’s a weird magazine too. I don’t remember seeing any .50 mags with that much taper before

  • The real question is, where are the optics?

    • Kelly Jackson

      He quick scopes

    • Porty1119

      I’m wondering if it’s intended to be used as a close-range antivehicle weapon and therefore sights aren’t desired/seen as necessary? Or perhaps the optics simply weren’t mounted. Who knows; drug runners are an odd bunch.

      • Dan

        They’re still trying to figure out how to get two magnifying glasses and a papertowel tube to work.

        • Lonnie

          duct tape and baling wire, works like a champ

      • Chameleon

        Maybe a pieced together BS rifle…as in FAKE.

        I’d like to see the action before I’d say its real. Even dope runners know to take care of their weapons but this “thing” looks like it’s seen better days in a scrap pile. For what these things cost, even dope heads would at least oil the da mn thing.

    • All the Raindrops

      Probably in some Brazilian cop’s dresser drawer

  • Jay

    Almost looks like someone mixed the Armalite AR50 with a Mcmillian Tac-50. Making their own chasis. My first guess was the AMSD Nemesis .50 (no longer manufactured) but the receiver doesn’t match. Maybe a SAKO 50.

  • Anton Gray Basson

    Thats a Truvelo .50 made in South Africa, Ive had the chance to shoot and it is an awesome bit of kit

    • iksnilol

      Nah, doesn’t quite look like it. The Truvelo doesn’t have as long a magwell as this thing has. Also it doesn’t have the tube thingy under the barrel as a forearm.

      • Anton Gray Basson

        The SR 50 doesnt, the CMS 50 does They normally put rails on it but youre right, closer look on the pc and its not right

  • Jolly

    McMillan tac 50. Bet a dollar

  • Enzo Baldwin

    +1 to Homebuilt Steyr Clone. The surrounding countries like Argentina and Bolivia use it, as well as the Brazilians, giving a template for a home built. Brazils arms trade isn’t extensive enough for it to be anything exotic.

  • Yohei556

    I know ive seen this before, because i remember that cheekpiece/shield. I think it was in a Shotgun News, when everyone was trying to crank out their own .50

  • ghost

    Looks like a big freaking gun. (that’s a technical term).

  • Southpaw89

    I have to agree with those suggesting that its a one-off. The barrel appears to have some surface corrosion on it while the receiver looks to be fairly clean. Suggesting that maybe the barrel was purchased surplus and a receiver was custom machined to fit it.

  • Nothing to do with a Steyr HS50 design. More likely a clone of the design that’s shared more or less by the French-made PGM Précision “Hécate II” and the Swiss SAN-511, ASMD OM-50 “Nemesis” and B&T SPR rifles.

  • DIR911911 .

    it’s the new kit for your ruger 10/22

    • Mystick

      The 10/52…

      • Roadrunner0


    • Mitche

      I’ve been waiting for this! You know where I can get one?

  • Grzegorz Widera

    AI50AW clone?

  • Dan

    Aside from having a magwell i don’t see the resemblance to anything but the AR-50. It doesn’t look like a steyr or a McMillan. Definitely a homebuilt weapon and if it works and is reliable not that bad of a job.

  • Lonnie

    To me it looks like a T50 Plasma rifle in the 1.6 gigahertz negative phase, reverse polarity, with loudener suppressor configuration. Mostly used on Ceti Alpha 6 to hunt wild Peterdactyls. But, the hand grip looks to be in the wrong location so, it is obviously a knock of drone clone. Thank you for your support.

    • Mystick

      No no no…. it’s obviously a phased plasma rifle in the 40 watt range….

  • Lawbob

    They smuggle parts / guns / ammo from Venezuela and Bolivia via rivers. Once internal to Brazil they can transport via car or other ground operation.

    Civilians can only own up to .380 handguns and rifles that shoot handgun cartridges. And shotguns. And only 6 total so I’d be way illegal there.

    In rio, as these pages often show, they are constantly finding m60s, hk91s, fal, etc. the ammo itself is contraband of course. All smuggled (or “donated” by military friendlies).

  • HKGuns

    It is definitely the highly sought after Remington 870 pump action 50 BMG.

  • Japanese Gun owner

    I always wondered how do the thugs in Brazil get such good weapons?
    they seem to me better armed then the Mexican cartels in North America.
    like that one video that showed a car that had 900 glocks in the center console WTF!

  • Clyde Bower

    How about it being a heavily modified Armalite AR-550?
    I would like to know how whoever called the markings to be “fake?” I would imagine that the markings were hand stamped due to the uneven quality. The rest could be a “one off” from Armalite (I’d put my money on) or again, the handy work of a gunsmith.

  • Roadrunner0

    This looks like an early light weight military prototype that was UUHMMM lost.. Back when we played in the jungle doing black op’s. interdicting the drug trade this may have been a primary operators weapon.. We did loose several teams back then working out of Panama but as SOP they were disavowed.. The sole negative to this would be that it had markings, but a company trying to get a contract may have overlooked that detail in a rush to deploy it as a field test down there.. Then the operator took it on a FI and lost it or was lost himself.. This is prototype #1 made the 53rd day of 1976……

  • T Sheehan

    People (other than vets who have been to Haji bazaars) don’t understand, or wildly underestimate the bootleg manufacturing capabilities in the 3rd world. They have whole name brand ecosystems making bootleg TV’s, Phones, and vehicles that Americans never see. Making a functional .50 bolt action isn’t remotely shocking.

    • Chet McFetter

      To quote the Zohan, “It’s got Sony guts”.

  • Secundius

    It looked like a Modified Boys 0.5625 (14.3×97.79mm) Ant-Tank Rifle, to me…

  • Adam

    Looks like the Brazilians have imported some Filipinos from Danao or some Pakki’s from Darra and set up shop…

  • Jesper Rex Andersen

    A Company named “kammerdeinerguns” made a conversion of the AR50, to take magazines, from the Harris M96.

    I have found several mentions of the company, but never any pictures. Maybe it is one of their converted AR50’s

  • Tothe

    It’s not a Maadi-Griffin. Beyond that, I have no idea.