A BMG For The Masses: The Serbu RN-50

We are continuing our “catching up with Serbu” coverage this week with a quick look at the RN-50: an affordable .50 BMG rifle. It was released about six months ago and somehow never hit the TFB radar, so I am making up for lost time by taking a quick look at its unique attributes. For one, the RN-50 is a modified break action rifle with a screw cap breech. The single shot system is a simple yet elegant design that will help you save money on ammo by (involuntarily) limiting your rate of fire.

Alternative aesthetics aside (I actually like the way it looks), my only real issue with this long-range banger is that getting a propper check weld looks to be challenging without a stock upgrade of some sort. Otherwise, if I had the land for it, the RN-50 would be a fun long range setup for around $1K, which is unmatched in the BMG world.

Serbu RN-50 @TFB

Serbu RN-50 @TFB

Serbu RN-50 @TFB

Serbu RN-50 @TFB

Serbu RN-50 @TFB

Serbu RN-50 @TFB

Serbu RN-50 @TFB

Serbu RN-50 @TFB

Serbu RN-50

  • Caliber: .50 BMG, .50 DTC for restricted markets. Other cartridges possible with barrel change
  • Action: Modified break action with threaded breech
  • Weight: 17 pounds
  • Barrel: 29.5 inches, alloy steel with 1-in-15 button rifling
  • Chassis: Heat-treated steel and aluminum construction
  • Finish: Manganese phosphate and hard anodized
  • Status: In production. Shipments started 5/17/16.
  • MSRP: $1199.00



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LE – Science – OSINT.
On a mission to make all of my guns as quiet as possible.
Twitter: @gunboxready
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  • iksnilol

    Yeah, no. Rather spring a couple of hundred bucks more and now have to depend on a threaded breech end to keep you safe.

    + it is slow and cumbersome to use.

    • Duray

      The breech cap locks against the receiver when closed.

      • iksnilol

        Still, it’s a clumsy and awkward design.

        • Ken

          Eye of the beholder. I’m more of the thought that, based on what it is, it’s quite an elegant design.

          • iksnilol

            It’s elegant to have to halfway disassemble the gun to load it?

            A far more elegant design would’a been a rolling block action, and its ergos would be much more suited for the kind of shooting one does with a .50 bmg.

      • marathag

        rather see a monstrous upscale of a falling block to do the same thing, without the cap

    • Giolli Joker

      I trust a threaded breech… it’s a very common mechanical feature with well known properties. Part of the cost saving could be in the fact that in designing phase they just needed to refer to pressure vessel specifications to get the data required to have a safe and strong breech.
      The receiver support is probably more to:
      -give a positive confirmation that the breech is fully closed (by preventing the barrel to realign if the cap isn’t in closed position);
      -reassure the shooter of the overall strength.

      • noob

        Imagine losing your threaded breech cap in the bush. I guess at the range it is okay because it will just fall on the floor.

        • Giolli Joker

          Yep, it is a range toy…
          The cap may fall during handling, but unless you drop it from a tree stand I don’t think you can easily lose it… it’s a fairly hefty piece of steel.

          • noob

            hmm I wonder how hard it would be to have some kind of metal loop for a length of paracord to tie the cap onto the rifle. That way it’s always attached even when unscrewed.

          • Giolli Joker

            Like an old style sink plug…

    • JSmath

      I feel like I’d much rather have a percussion cap .50 than this thing.

      • BearSlayer338

        You could probably reload that faster too.

  • Martin Grønsdal

    All the wheelchair-commandos are like… threaded breech, not tactical enough.

  • Stephen Hubert

    Budget .50BMG? Pass.

    • marathag

      Nah, there’s a place for this.

      • Dan

        Yeah, Syria….Iraq…Afghanistan

        • marathag

          and BFE, USA

    • John

      Agreed. If I were to buy a rifle in .50 bmg I want it overengineered, not going to blow myself up with half baked contraptions

      • SGT Fish

        yeah, cuz all those artillerry pieces with interrupted thread breeches are half baked too

        • John

          Who said it was the threaded breech I had a problem with?

          • TennTexan

            What makes you think the RN50 will blow up in your face? Threaded breech is an extremely strong design, and Serbu has many, many years of experience making .50 BMG barrels. It might be ugly, but it’s a solid, safe design.

          • John

            Again, Who said it was the threaded breech I had a problem with?

          • TennTexan

            I’m just trying to figure out what you DO have a problem with… care to enlighten us?

  • marathag

    Not much more effort to do an interrupted threat breech, that would be nicer than full thread

  • me ohmy

    actually it looks like one of those retarded ass slamfire cobbled together guns that moron on youtube makes and make refined the basic premise..
    this idiot, who knows Mark Serbu…augh
    on youtube royal nonesuch

    • Giolli Joker

      What do you think RN stands for?
      It’s a collaboration between Royal Nonesuch and Serbu.

      • me ohmy

        Mark Serbu makes such great stuff..

        • Edeco

          Game recognize game.

  • Giolli Joker

    “The single shot system is a simple yet elegant design that will help you save money on ammo by (involuntarily) limiting your rate of fire”

    I kinda guess that the rate of fire (or the total no. of shots per session) of a shoulder fired .50BMG is fairly low no matter the presence or not of a magazine…

    • Gary Kirk

      You’d be surprised, the Barrett is pretty smooth recoilwise.. About like a 12 3 1/2″ mag.. However the original 50BMG bolt guns, McMillan..
      Were miserable to be behind..

  • ozzallos .

    Dat spot weld…

    • Ken

      “dat” ain’t a “spot weld”

      • Burt Maclin

        Yup, those are definitely TIG welds using nice technique. Unfortunately they did not properly do the start/stops of the runs. They didn’t go back over them with a little extra material, and as a result you see those pinhole craters. Those are the weak spots and will eventually (sooner rather than later) form cracks from all the pressure put on them.

        I honestly can’t believe anyone with any sort of welding knowledge would post those photos and be proud of them….

        • Gary Kirk

          #fail piont

        • Ryfyle

          Wel you could drill them out and tig it yourself. Or you could go RN and go nuts with so E-6010 rod at maybe 50 amps.

          • tts

            Sure but $1K+ gun you’d expect stuff to be done right the 1st time.

          • me ohmy

            nothing cleanses like FIREEEeeeeee
            even mitigated weld quality

          • dltaylor51

            Use 70-110 low hi and it will never break

      • Baggy270

        Dat a “check weld”?

  • micmac80

    all you need now is a cheap enough glass that will take recoil that has been known to break even quality optics in short order.

    • AK™

      SWFA fixed power optics.

  • Doctor Jelly

    I could have sworn I saw an article on here when it was available at the pre-order price of $875… I briefly considered it, but still balked at what I was getting for the price. Why would I want such an awkward design and a ridiculous caliber at the now price of $1200 when I just saw a Savage 112 in a mildly less ridiculous chambering (338 Lapua) with a conventional bolt action design (single shot too) for $775? I still can’t justify such a large caliber as 338LM, but if I needed one on a budget, the Savage would absolutely be my pick over this goofy setup. I get what he was going for, but the price point was the justification for such compromises, and that was missed considering Safety Harbor has a single shot 50BMG upper for $250 more that drops onto an AR lower and functions/looks more conventional…

    Besides, I’m not overly a fan on Royal Nonesuch. Not that I don’t like his builds, I just don’t like that over all these years he doesn’t seem to have grown more competent. It’s disappointing to me that the majority of his builds still feature bird s–t welds and simple slam fire setups…

    • HenryV

      …..because .50BMG is magic. 🙂

      (Disclaimer: You are right. I was joking. Comments on gun blogs are often inhabited by the small of brain who don’t understand humour.)

    • Frank

      The better question to ask isn’t “why?” It’s “why not?”

  • Arie Heath

    Royal Nonesuch, you magnificent bastard. I just might pick one of these up to use as a range blaster.

    • Gary Kirk

      Looking at the construction, might just blast your range.. By all means, have at it..

  • derpmaster

    Serbu’s single shot bolt 50 is probably the most common 50BMG in civilian hands because it’s cheap. This thing will probably outsell it’s older brother 2-3x based on price alone.

    I want one.

    • Gary Kirk

      Price wise, maybe.. But most common would probably be the M99 Barrett.. Just for time of existence..

    • John

      I would’ve thought that would be the 50 SHTF. Would think people would spend the extra $300 to get a bolt action

  • wetcorps

    Pistol version when

  • Ark

    $1k? Looks like it was built by drunken Slavs in a back room at a tractor factory.

    • iksnilol

      Why insult drunken Slavs? We make better quality than that.

      • Gary Kirk

        Yeah, this is drunken Florida red neck work at it’s finest.. Stick with my Barrett..

    • Pod

      It’s a mass-market version of one of the crazy homemade guns Royal Nonesuch builds. Hence the “RN” in RN50…

  • Mystick

    Still prefer the Watson’s Weapons .50 AR upper…

  • Gary Kirk

    Yeeeaa… NO..

  • This gun reminds me of Kung Fu, because in fact it is a little bit frightening.

    • Klaus Von Schmitto

      Reloading this thing isn’t as fast as lightning though.

  • 22winmag

    One shot, one kill, right?

    For those of you without artillery experience, the name of the game is shoot and scoot. Take your shot and having given away your position, get the hell out of Dodge before the counter battery fire rains down on your head.

  • Pod

    OK, this has my interest. And I’ll be blunt, I’m gonna let these things be in the market for a bit before I think about buying one. I’d like to see somewhat of a proven track record of real-world safety.

    That being said, unfortunately I can’t think of a place around where I live (South Florida) where I could really let it shine. There’s a gun-club style range in Homestead which has a 500 yard range, but I’m not sure if they just let people show up to shoot. And certainly none of the indoor ranges will allow .50 BMG, even for s–ts and grins.

    • TennTexan

      The threaded breech cap is probably one of the strongest designs Serbu could have used. It may not look like much from an appearance standpoint, but the RN50 does look like a very solid, safe design. I’d have no reservations about pulling the trigger on one.

  • Ryfyle

    This makes me want to build a Super Mosin and Sell it.

  • Broz

    This thing needs an interrupted thread, same as on artillery breeches (or the Weatherby bolt system), with a short throw ‘handle’, for quick detachment of the breech cap

  • Broz

    IIRC Hank Strange has a brief teaser in one of his videos a while back…

  • Edeco

    I’m happy Nonesuch is staying active, branching out, but it seems the price has gotten significantly less impressive which undermines the perverse beauty of the whole thing.

    Anyone else recall the Birdman Weapons “Jaded 50”?

  • JoshCalle

    So, why can’t it be a regular break action, like a really beefy version of the H&R handi rifle? The whole screw off breech is kind of a turn off.

    • TennTexan

      Because a regular break action would probably not be strong enough for .50BMG. The threaded breech cap is necessary due to the pressures involved.

  • Lou

    I totally get what Serbu & RN are trying to accomplish – a .50 BMG that almost anyone can afford. The screw in breech is something I could live with (and is VERY strong regarding pressures) as this is not a house to house urban warfare weapon BUT they missed the boat with that $1200 MSRP. Sure, street price could be around $1,050 but once I’m up that high, I would rather shell out a few hundred more and get a .50 BMG upper which drops on one of my AR-15s. If they could bank roll a run of a couple thousand of these and get the price down to a $650 – $750 street price range, I would grab one today and so would the others who don’t like the screw in breech. They probably have “opened the door” for a larger manufacturer who can finance a run of 5000 to copy their idea and come out with a very affordable .50 BMG.

  • Cal S.

    $1,200?! Well, any slight appeal a single-shot, deconstruction reload rifle had for me is gone. I could get a single-shot bolt action upper for just a couple hundred more. It would be worth the investment!

  • LazyReader

    Holy Jeez, this thing looks about as well made as a Tec-9 in the 80’s.

  • Jeff Brown

    So I can afford to buy a rifle I can’t afford to feed? Right?

    • Rick O’Shay

      I thought it was chambered for .50BMG. Turns out it’s chambered for $5 bills.

    • TennTexan

      Wal-Marts here in Texas sell American Eagle .50BMG. It’s not that expensive. Plus you can always reload.

  • Ambassador Vader

    Hahaha it’s a 50 bmg pipe gun! I get that 50’s are just inherently expensive but where are they getting their cost build up here? Granted the barrel has to be the most expensive cost but i would love to see that materials list. All b@ll busting aside it is nice to see them atleast trying.

  • McSquizzy

    Does this weapon have any way of venting excess pressure in the event of a ruptured primer or cartridge case? Or is it simply made strong enough to withstand excess pressure?

  • wtflol

    Why they don’t want to copy PTRD? It’s cheap to produce and much more than this piece of Nonesuch-stuff.

  • wtflol

    *much more reliable than this

  • dltaylor51

    I consider the Armalite AR 50 to be the starting point for someone looking for a good entry level 50 that will hold its own against any other brand or design at a thousand yards.I’ve had one for over four yrs.and know from experience that this is the most bang for the buck you can buy.Nightforce is the only scope that will stand up to the repeated bashing and not break but any scope will work for a while, if you go El cheapo on the scope buy two of them so you always have one on the gun while the other is in the hospital being repaired.Lee makes a loading press kit for the 50 BMG,get one and roll your own or you wont be able to afford to shoot it.

  • lurpy

    I’ve always wanted a .50 BMG zip gun.