MSBS-5,56 (Modulowy System Broni Strzeleckiej kalibru 5,56 mm)

The latest prototypes of the future polish service weapon, the MSBS-5,56 (Modulowy System Broni Strzeleckiej kalibru 5,56 mm), are looking very nifty.

The MSBS-5,56 family is being developed by Radom’s Fabryka Broni Lucznik and the Military University of Technology (WAT). The core component of the family is a common upper receiver. Components will be able to be added or removed in order to turn it into a carbine, assault rifle, designated sniper rifle or light machine gun. What differentiates it from the latest generation assault rifles such as the FN SCAR, Bushmaster ACR and Beretta ARX is that it can be configured in either a traditional or bullpup configuration.

Not pictured is the GPBO-40 underbarrel and GSBO-40 stand-alone grenade launchers which are being developed alongside the MSBS.

[ Many thanks to REMOV for sending me the photos and information. ]

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.


  • Rob

    Jeez. It looks JUST like an ACR. It’s like a bad carbon copy.

  • Nethenial

    This thing obviously has some ACR inspired roots, I wonder how magpul will feel about it?

  • KP

    That’s interesting but it’s not too new of a concept. The M14 can do the same trick with a different stock turning it into a bullpup. The SKS has a few and even the Mosin’s got one of those.

    I only bring that up because I don’t see the point of having an army that has both setups. If you train some on bullpups, you should train all in my opinion. I think this gun looks like it was made for export more than for national use. Not that that’s a bad thing or anything like that.

  • Mad World

    That is WAY more nifty than the ACR! The ACR has nothing on that as far as being nifty goes! haha

  • Mad World

    Does that thing take Styer AUG mags? If it does then it would be spot on down here in NZ, pleanty of cheap ex army AUG mags floating around, AR/STANAG mags go for over $150nz versus $25 for an AUG and on that note I am hoping for a Civvy Semi version.

  • subase

    Oh please, just because it has a furniture resemblance doesn’t mean squat. Your all acting like HK (when the accused the mexicans of copying their g36).

    This rifle can be switched into bullpup format, can the ACR do that? No.

  • Mad World

    well said subase. You can hardly compare aftermarket stocks for outdated gear to a modular system like this intended to function as either, seems a good idea also settles the traditional or bullpup debate, train the soldier on both and let him decide. Great idea.

  • AFAIK it accepts standard NATO mags.

  • Sian

    I’d like to see the charging handle further forward, especially on the bullpup configuration. An ejector switch like the Beretta’s would be even more welcome here too.

    Aside from bare aesthetics, I see more mechanical resemblance to the G36 family than anything ACR/SCAR.

    The common upper is an interesting way to go. It takes a bit of staring to really see it.

  • Eurogunner

    Copy of this, copy of that, so what?

    European and Asian manufactures will copy all American gun products sooner or later because there’s demand but no supply.

    Why there’s no supply? Because state department has blocked practically all export channels for guns and gun accessories. So, if magpul or magpul fans feel bad about the fact that someone is copying their ideas, they should address their complains to state department that prevents U.S. companies doing business with potential customers outside U.S.

    Would be nice to buy ACR or SCAR also over here, but they are for U.S. customers only. So, there’s demand but no supply. And when there’s demand, supply will appear. All American gun products will be copied sooner or later.

  • Freiheit

    It looks like this might need the same shooting discipline as a revolver. Keep your thumb BEHIND the flash hider.

    • Freiheit, it is a mistake never made twice 😉

  • Nanban Jim

    Don’t sleep on the Polish small arms industry. They’re doing a repeat of their innovative 30s, but this time they aren’t being invaded.

  • R N

    This is so cool, yeh lit looks ACRish, but thats the gun industry for you
    anyway the bullpup to standard is awesome I lov ehow that works, yeh you can get stocks for rifles like that, but I think this is the first I’ve heard of coming out of the box with both options

  • Jim

    Might I ask if modularity is really desired in the modern military? I mean it’s not like you’ll be converting soldiers from front line infantry to snipers at a moment’s notice, and we can also suppose that a jack of all trades rifle isn’t going to do either job as well as two purpose built rifles. So what’s the point?

  • Tuulos

    Eurogunner, it goes the other way too, USA copies plenty of stuff from Europe & Asia too. And in firearms business it isn’t even that strange, because most designs usually are based on older designs. It luckily seems to drive the manufacturers to compete in quality & price of the products, with the added benefit of some truly unique designs every now and then.

    And you are sadly only too correct on the ridiculous export regulations.

  • KFin

    Looks like another interesting 21st century carbine that I want.. I really dont care who copies who, copying means that a system is usually sound and in demand, and ill grab up both if I can, I love bullpups which is why I grabbed and MSAR instead of an ACR, capabilities of both rifles are almost identical (caliber swaps, etc..) and the fact that the MSAR is legally a pistol in michigan, making it legally concealable as a vehicle weapon

  • Vitor

    If they manage to copy the quick change of ejection from the Beretta ARX, it will be a win.

  • gunslinger

    I don’t get the “can be a bullpup or carbine”. i’m trying to see what is the same on both and different. from what i can tell, and please someone correct me if i’m wrong, is that the outer casing (the green plastic) is just a shell, and the barrel/receiver/sear, etc is inside. and that is the part that is actually transfered between configurations. right? and if so, does that mean you get both “housings” when you get the rifle, or do you have to buy 1 and then the extra housing seperately?

    now i haven’t been on the BP/CB debate, but i can see where one could be better than the other. so i ask why not be capable of serving either function, so long as the provisions are there.

  • Caliber .223 is a mistake, nothing under 6.5mm worth a dime! The polish should stick with the 7.62x39mm WARPAC carbine ammo, even if they want a new infantry weapon instead of the AK.

  • tothjr

    I think that this is an awesome idea.
    I hope they can succeed where Magpul failed and create “the peoples” rifle.

  • Lance

    I not surprised that Poland being the only former east block country to adopt a 5.56mm AK to look for a replacement. Most East block nation experimented with a AK-101 and never got satisfactory results. Going with a new design will work in these conditions.

  • Rob

    Okay America, time to upgrade.

  • jdun1911

    I would like to see the internals.

  • Dee


    Correct me if I’m wrong, but in most of Europe(Switzerland an exception) isn’t Civilian ownership of firearms illegal?? OR technically IS legal but is SO OVER regulated, restricted, and expensive that’s it’s practically impossible for a Law Abiding Citizen of the EU to own a firearm?? Also aren’t many types of firearms such as Semi-Auto rifles like AR-15 and AK-47 type rifles that are legal for American civilian ownership, is just plain illegal for civilian ownership in Europe?? Doesn’t the Media and various Governments in the EU Promote Anti-Gun Legislation/Views SO HEAVILY, that the general public in the EU think gun ownership is “unnecessary, extreme, barbaric, crazy, and for only Warmongering Americans??”

    Also, isn’t Anti-Americanism so rampant throughout Europe(and the rest of the world) that even if American Firearms were available as well as European companies, wouldn’t people CHOOSE to purchase a European Firearm instead than an American brand because we’re hated SO MUCH, that they would choose to support a European company opposed to an American company??

    I can potentially see European Military/Law enforcement as a Lucrative market, BUT again, because of Anti-Americanism, wouldn’t a European Manufacture be favored over an American one?? Believe it or not in the USA, Firearm Companies don’t make most of their money from contracts with the Military or Law Enforcement, they make their money from American Civilian sales. Civilians keep them in business and give them a steady flow of money for future Research & Development.

    Europe doesn’t sound like a lucrative market for American Firearms Companies. I think the market is TOO small and there’s too many obstacles(Anti-Gun Legislation, Anti-Americanism) that need to be overcome for Europe to be a potential market for American Firearms Companies to consider.

  • Redchrome

    Indeed it looks very ACR-ish; but imitation really is the sincerest form of flattery. There’s a limited number of ways to do things well, and very few that are really good. Whatever it’s other flaws may be, the ACR does have some really great modular design concepts.

    These examples look like non-firing test articles tho… solid pieces of plastic. We’ll have to see what the eventual result looks like.

    Being able to convert from bullpup to conventional layout has its advantages. bullpups really do have a lot of advantages, but a lot of drawbacks as well. Some users will want them; some will not. (IMHO a lot of it comes down to whether you’re going to need to shoot left-handed around the side of a building; but I’ve not been in combat so this is just my armchair-generalship). Options are a good thing to have.

  • heh


    My SIG 550 with fun button and naughty bits, available without selling my ass to some alphabet soup government bureau, speaks otherwise.

    Please don’t tar ‘europe’ with the same brush as one would for the UK and several countries’ firearms laws, it is one of the reasons why Americans are viewed by some with slight distaste in general.

    Sure, American gun companies make most of their money from civillians, but that’s because a lot of the big contracts have been taken up by European companies, or their American branches. Also, I don’t think Colt really likes selling to civilians, no?

    Thank you.

  • Dee


    It wasn’t my intention to “tar Europe” all the same, I apologize if i came off that way. I’m sorry. I have difficulty expressing myself through text on the internet sometimes. My Long-winded post was trying to express that even if the US State Department allowed the exportation of American Firearms to Europe that it would be futile to try and make a profit, due to the political environment/culture in Europe(Anti-Gun Legislation/Sentiments, Anti-Americanism). If I’m totally wrong, Please provide examples of countries in the EU where it is legal for European civilians to purchase and own the same firearms that American citizens can, for example:

    1911s, Glocks, Sigs, H&K pistols, Revolvers, etc.

    Semi-auto versions of submachine guns:
    MP5, UMP, P90, etc.

    Semi-auto version of assault rifles:
    AR-15, AK-47, Steyr AUG, H&K G36, Sig 556, etc.

    Tactical Pump shot guns(NOT Hunting shotguns):
    Remington 870, Mossberg 500/590, Benelli, etc.

    Tactical Semi-auto shotguns(NOT Hunting shotguns):
    Remington 1100, Mossberg 930, Benelli, Saiga 12, etc.

    Precision/Sniper bolt-action/semi-auto rifles:
    Remington 700, H&K PSG-1, Draganov, Barrett 82A1, etc.

    Colt doesn’t like selling to civilians?? hmmm, i never really got that impression from them(although they are busy fulfilling military contracts right now, right??), i guess i’m crazy. If anything H&K loathes civilian customers(customer service), although this isn’t my personal experience, only 2nd hand from my friends who own USPs, P30s and HK45s.
    I own a Colt AR-15 6920 and a 1911 XSE and I’m very satisfied with both weapons(although i wish my 1911 came Dehorned from the factory).

  • Lance

    @ Rob

    We are upgradeing the M-4!

  • Dee

    whoops, take off H&K PSG-1 and MP5, those aren’t available to civilians, i don’t think..

  • jdun1911


    Colt sell quite a number of different firearms to the general public. They are a pro civilian company. However there main customer is the US military first and foremost.

    Bullpup has only one advantage and that is a long barrel length in a compact size. Everything else it does much worst compare to traditional stock. It give up so much for so little. That’s why special forces and private contractors don’t use them.

  • Chris

    @ Dee.

    They are. But getting a hold of either are going to cost a pretty penny. Well over $10,000 for the PSG-1 and much more for an automatic MP5 (where legal). There of course are semi-auto MP5 variants as well, but genuine the HK’s are worth a good lot.

  • jdun1911

    Ops. I mean heh not dee on my last post.

  • Lance

    I like that you can choose between bullpup or ormal and customized weapon for each solder per his pike not to cram a too small bullpup into a big guy or vis versa.

  • KP

    I wouldn’t call this an ACR clone as almost all rifles modern rifles are based on the AR-180 which is a short stroke gas piston pushing on a bolt carrier group that’s on a rail that is mounted in an aluminum receiver. The main variation these days is whether it’s short stroke or long stroke, so I really don’t call anything a copy of another.

    I still think that the concept is interesting but is more applicable to individualistic end-users rather than military force. If they wanted to be really innovative, in my opinion, they would have had it as a forward ejecting rifle so it could be fired left handed in bullpup mode. FN and maybe others have devised bullpup forward ejecting systems but there could be more, better ways of doing it. Having a stock chassis system that changes a rifle from conventional to bullpup is not what I consider innovative.

    As far as not lumping this in with antiquated weapons getting new looks from bullpup conversion stocks – well, in all honesty you could add a trigger rod to a G36 and put the trigger group in front of the magazine. There’s really nothing stopping anyone from doing that other than an unwillingness to do so (market considerations and cost/benefit stuff) and for the fact that scenario more or less exists in the L85A2.

    Looks like a neat gun – doesn’t bring anything to the table that I find particularly interesting.

  • Tuulos

    Dee, they are perfectly legal in most if not all of the Nordic countries and most of the other European countries too. It might be worth to note that most of the European media seems to be leftish so most of the hate for the USA comes from there. Most of the shooters don’t hate USA, in fact you would be hard pressed to find one that doesn’t own a gun or gunpart either made or designed in USA. And while buying the gun (because of the permit needed) is somewhat harder here we are not limited on imaginary evil features. Hell, we can even buy suppressors without tax stamps.

    Of course, there are some differences here because Europe is not a single huge country so some countries may have considerably tighter gun laws (ie. UK) and some more lax.

  • Wosiu

    Please pay attention to the fact that this MSBS-5.56 in bull-pup carbine version with abt. 10″ barrel, has OAL abt. 20.5″, which is only slightly longer than failed Magpul PDR project planned with 10.5″-12″ barrel and 18″-20″ OAL!

  • Colin

    I’ve been following this project on, you can’t convert from bullpup to convensional. They are building/testing both (with common components) before deciding which style to adopt…

  • ko5ma

    The point that you are missing here is that it’s more of a technology demonstrator/early prototype than anything else. What you see on the pics is just a plastic mockup, the mechanical part was tested recently was an older design (you can see Remov’s video here: and will actually need major changes before being able to even fit inside the new shell. It is not decided whether the weapon will be actually issued by the army, and if so – in which version. The process will take some years, so don’t get your hopes up for a civilian version anytime soon (if ever, it’s Łucznik after all ;P).

    @ Tamas Feher
    The caliber is a NATO standard whether you like it or not, and let’s face it, no country will change it unless the US does it first.
    As for the 5.56 AK’s (Beryl) – not sure what are you talking about. It’s certainly an outdated design with many flaws, but it’s battle proven, works just fine and is rather liked by soldiers.

    @ Dee
    Most of the weapons you listed are actually legal in many european countries, including Poland, provided you have a license. Obtaining the license is another issue, but is certainly not impossible. As for “anti-americanism”, do you really believe what you’re saying? If so, no comment…

  • Harald Hansen

    Firearms are not outlawed in Europe. There are tighter regulations than the US in most European states (remember, Europe is a continent, not a nation), but some areas are freer than others. Examples: The Czech Republic allows people to carry concealed with no particular lisencing or reason required ( Norway and Germany (and maybe others I don’t know about) allows the ownership and use of silencers for firearms with no taxes or paperwork.

    There are areas in the US that are more regulated than many areas in Europe. Aren’t firearms outlawed in NY City and Washington, D.C., for example?

  • Clodboy

    What’s more, it is kind of hard to define what a “lax” gun law even is, due to those often being a convoluted, illogical mess.

    Take Austria, where pump-action shotguns are illegal.

    Double or triple-barreled barreled shotguns? Anyone over the age of 18 can get one.
    Autoloaders? They’re yours, if you’ve got a got a license.

    But pump-action shotguns? No sirree.

    So next time you watch “Terminator”, imagine how the famous gun shop scene would have played out in Arnie’s home country:
    Ahnuld: “12 Gauge Autoloader.”
    Owner: *holds up a SPAS-12* “It’s Italian made. You can go pump… or auto. Which means I can’t sell it to you. Can’t have you chamber a shell with a dramatic pumping motion now, can we?”

  • Kostas HK

    You would be hard pressed to find a European country with more constricting laws than Greece. We are not allowed ANY rifled longguns, not enen .22s. Only smoothbores with (53cm) barrels and longer and these with a lot of red tape. Pistols are even harder. Only cops and people with connections because at any time they can reject your application for a ownership permit WITHOUT JUSTIFICATIONS. Relics of the Greek civil war ’45-49 (fear of…revolution) continued by leftists governments and police leaderships who dont civilians owning guns, even legally. So consider yourselves lucky.

  • Vitor

    KP, I believe that the quick change of ejection side of the Beretta ARX made foward ejection obsolete. Foward ejection looks cool, but it requires some extra enginering and demands an old fashioned tilting bolt to work properly.

  • Mike

    I think the bullpup already got dropped from the program…It is just going to be the normal rifle.

  • TE

    @ Lance.
    The US Army is looking into both, A possible M4 upgrade and A possible Replacement all depends on who shows better

  • jdun1911

    Here the thing about regulation. Who can get them? The common man? I don’t think so. Well not in the majority of the cases. In the USA it doesn’t matter if you’re poor, middle class, rich, color, race, religion, etc as long as you aren’t a felon, wanted by the police, or a traitor you can get a firearm. Hell you don’t even need to be a US citizen. That’s the difference between US and European, equality.

    IIRC Brady campaign president (gun control group) has a conceal carry permit in DC. Yet the common man cannot in DC. That’s corruption, that’s control. Only the elite can have and the common man be damn. Fuck them.

    I live in Va and in my state, if you’re military, ex military, ex law enforcement as long as you’re not a felon, wanted by the police, or a traitor you just fill out the conceal carry form ($50 fee for five years) and in a month or less the judge will approved the permit.

    For the rest, you have to take a two or so hours class than applied for the permit. The judge cannot denied for any reason other than felon, wanted by the police, or a traitor. This is what I called equality, it something that the left preached a lot but never do.

    • Guys, please stay on topic.

  • Lance


    Most think the replacement comeptition is a Farse since only the army is doing the competition and that the Army is already buying new M-4s and that the army isnt giving out requriments now anyway.

  • Tom Stone

    Modularity has a lot more to do with training, servicing and repairing the weapon than providing the individual soldier with the option to switch from a PDW to a sniper configuration. Easier to train your armorers,simpler supply chain.

  • Chortles

    “failed Magpul PDR project” – Wosiu

    That ‘failure’ was Magpul putting the PDR on the backburner after the (US) military didn’t bother returning Magpul’s calls, regarding the proposal for a “subcompact” bullpup, since the military would have been the main (intended) customer.

    Then again, the last Magpul “technical specs” document I believe had its numbers date back to 2006-2007, years before the change in (at least the Internet would lead me to believe) attitudes regarding the effectiveness of 5.56 x 45 across range (read: Afghanistan).

  • Wosiu

    “I’ve been following this project on, you can’t convert from bullpup to convensional.”

    Not yet, but it is planned to convert from bull-pup to conventional and vice versa. This is the reason of whole idea of common upper receiver.

    “They are building/testing both (with common components) before deciding which style to adopt…”

    No. Despite of being based on government grant from Ministry of Science, this is not army project. Polish army may or may not adopt this system, but for sure complete system will be offered on export by Fabryka Broni Radom and by whole Bumar Group.


    “It is not decided whether the weapon will be actually issued by the army, and if so – in which version.”

    As above. Additionaly, please be informed that Bumar Group decided to build completly new production plant with most modern machines in Fabryka Broni Radom, for sure not for production of Beryls only…

    “The process will take some years, so don’t get your hopes up for a civilian version anytime soon”

    Civilian version could hit the market even sooner than military version.

    BTW, according to the some infos, mock-ups of MSBS-5.56 will be presented on SHOT Show 2011 in Fabryka Broni Radom boot, together with newest versions of Beryl with M16 magazine.

    • Wosiu, thanks for the info.

  • Colin

    @ Wosiu,

    I stand corrected on the project / funding. However I remain to be convinced that you’ll be able to convert from conventional to bullpup in the future.

    I look forward to be being proved wrong (again!)…

  • Majster

    Don’t sweat it. Classic/bullpup feature exists only to reduce costs of production and maintenance if you decide to adapt both. Bullpup version works better in tight space, so its better suited for special forces, vechicle crew’s and PDW role. If you wanted to produce 2 versions using separate constructions, you’d have to create new assembly line for bullpup. Wich would in turn skyrocket the cost per unit.
    About ACR-ish look.. well, to me it looks that external designers were simply out of ideas. Internally it has very little in common with ACR. Think logically:
    Poland is not China, we have to obey by the interantional law. If ACR producer would think even for a second that it’s a ripoff of his product, he’d sue Polish producer to every possible court. Americans aint THAT dumb you know…

  • Some Guy

    I think this is…


    Finally a gun that can both be an excellent carbine and standard rifle/marksmen/auto rifle without the debate and loss between the two types of systems.

    Sounds awesome.

    I wonder what the firing system is and how reliable it is…

    Along with the question of, can it be scaled up to a more “lethal” caliber…

  • Majster

    Of course it can… its all about $$$$

  • ksajad

    Dee a few words to you. Most Europeans like the United States. As for Poland, nearly 10 million Poles live in the states :-). May have referred a bad impression because sometimes the people of the United States behave very arogancko.Ale dislike you come to a brawl at the bar does not shoot. Law in the countries of Europe it is very restrictive. As for Poland, which has 40 million people. Firearms license apart from the police and the army has about 100 thousand people. On the other hand. Willing is only another 100 thousand people :-). We have a very low crime involving firearms. Greetings from Polish and sorry for the mistakes but I use google translator 🙂