New “Super Strong” Barrel Steel Released by Aubert & Duval

A US Marine fires a FAMAS G2 aboard the Mistral, a French amphibious assault ship. The FAMAS G2 is used by French Marines, and is seen here configured for left-handed operation. US Marine Corps photo by Cpl. Luke Hoogendam. public domain.

French steelmaker Aubert & Duval have announced a new high purity steel alloy that could allow future firearms barrels to be stronger, be tougher, and last longer. The steel, called “ARMAD”, is a 3% chromoly steel made with a similar composition to their GKH (33CrMoV12-9) steel used for small arms barrels, such as those used on the FAMAS rifle. Where ARMAD differs is in how it is made, rather than what it is made from. Aubert & Duval has developed a very precise process that uses both electric arc furnace and laddle furnace stages, which results in very low levels of impurities – significantly less than 50 parts per million of phosphorous and less than 5 parts per million of sulfur. The high purity results in a steel with a finer and more uniform grain structure, which means it can be heat treated to higher hardnesses while retaining its strength – meaning gun barrels made out of the stuff should last longer, while being both stronger and tougher than those made of more conventional steels. A technical article describing the new steel and the process to make it has been published by Forge & Fonderie magazine, but Aubert & Duval provided an English language document to TFB for publication:

ARMAD – TheFirearmBlog – Version 04

EDIT: Above link doesn’t work. Here is another link.

As this image shows, ARMAD’s refined process results in a much more uniform grain structure than other steel grades. ARMAD shown in the green box on the left, 32CrMoV12-10 on the right:

You can’t buy barrels made out of ARMAD just yet, but Aubert & Duval has sent material to several barrel manufacturers in both the United States and Europe for testing. Maybe someday, high hardness steels of this type will be standard for small arms barrels, who knows?

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


  • James

    Yeah, but how many arms and legs is it going to cost beyond using 416R or 4150?

    • Brett

      All of them. All of the appendages!

      • Dougscamo

        Don’t forget the first-born male child….

        • Flounder

          Males only? What is wrong with the ladies?

          • Gary Kirk

            Not enough “appendages”

          • ORCON

            Where we’re going we wont need appendages.

          • Dougscamo

            To paraphrase Mel Brooks…”Not Jewish enough”….

  • Ranger Rick

    Finer grain means smoother bores, smoother bores means higher velocity, less fouling and more accuracy in addition to longer barrel life. A win – win situation.

    • EzGoingKev

      Smoother bores do not necessarily equate higher velocity.

      • Honest question (I don’t mean to be snarkey) >>> How can less friction not translate into higher velocity…

        • ostiariusalpha

          If you have a squeezebore barrel with higher friction steel, it can get more velocity than a standard barrel with a low friction bore. The lower friction one will always be more efficient though. There’s lots of little tricks that can be used to increase velocity from a barrel of a given length.

          • Thanks… That makes sense. More friction = higher pressure = higher bullet velocity…

          • Johannes von’ Strauch

            *Only with the specific powder and charge! Less friction is more efficient, but just needs a bit more powder, or a slightly faster powder type.
            Adding powder decreases chamber volume and increase burning area so all propellant burns normal again, and the additional powder increases energy.

        • Paul Joly

          When you create a small vacuum between the surfaces like between two gauge block.

          • Qoquaq En Transic

            But two gauge blocks can slide against each other like butter. It’s strength is when one tries to pull them directly apart. That’s the vacuum.

        • Johannes von’ Strauch

          Actually yes that can indeed happen sometimes, with less friction and therefore reduced pressure, the powder meant to be burned at a certain pressure can tend to burn slower (burning characteristics changes with pressure), therefore creating even less pressure and acceleration, the charge then shall be increased, or powder type changed. Such also occurs if thou tend to use molybdenum disulfide coatings.

    • Klaus Von Schmitto

      I shouldn’t open this can of worms but – finer grain at the molecular level doesn’t really translate into a smoother bore. How much you polish the bore translates into how smooth the bore is. If you polished the most “granular” grade of steel to a 1uM finish it would be indistinguishable from the “finest grained” steel polished to that same surface roughness, except at the molecular level and no bullet would care one way or the other.

      The wear on the barrel is where the gain would be. IE – How long it retains that polish.

      • Edeco

        Hmmm, yeah I didn’t want to get into it myself, in tribology I’m basically operating in the level of superstition. But yeah, not sure it would be smoother. Or that smoother is always lower friction, especially when something is held around the girth and humming along. Not sure what effects are prevailing.

    • J-

      Nope. The final bore smoothness is a function of the machining operations. Then if the barrel is chrome plated or FNC that alters the surface as well. The effect of grain size on surface finish works on a very high polish and chemical etching.

  • Good news for high performance calibers. Would be great to see this in .22 Nosler, 6mm Creedmoor, etc.

    • iksnilol

      Or 6.5×55.

      That cartridge can be brutal when loaded hot.

    • Edeco

      I’d love to see top velocities increase again. One might say we’re creeping up, relative to the sectional density, with 6’s and 6.5’s. But to see the mid 4,000 fps range tamed would be nice.

      • 4,000 is getting greedy! I’d be happy just to see anything in 6 or 6.5 hitting 3,000fps with a 18-20″ barrel.

        • Run

          3000 from 20″? Lousy

          • That’s what I thought initially, but RifleShooter (a truly fantastic resource btw) has done numerous barrel chop tests on various calibers, including .243, 6 and 6.5 Creedmoor – which are considered to be pretty hot rounds that are hard on barrels.

            6.5 Creedmoor 120gr AMAX 20″ = 2819fps; 142gr SMK = 2609fps
            6mm Creedmoor 107gr SMK 20″ = 3000fps; 95gr = 3061fps
            .243 Wichester 100gr 20″ = 2715fps

            Hence why I think 4000fps is pretty greedy 😉

          • ostiariusalpha

            6.5 CM isn’t as kind on barrels as .308 Winchester, but it’s hardly a barrel burner at only 21.5 kJ/cm² of heat flux. I certainly wouldn’t use it on a select fire gun, but in a bolt action it sits in a very nice compromise between performance and barrel life. And why limit yourself to the .308 Winchester parent case anyway? The 6.5-284 Norma gets that 120gr up to 3000fps easily enough. Of course, if you want to boost velocity and decrease barrel heat flux, there’s always our old friend the sabot.

          • It would be great to see R&D put into sabots again. A saboted 100gr 6mm copper VLD @ 3400fps from .308 case would be a great round.

          • ostiariusalpha

            Even current cup sabots are pretty decent, but there’s always room for improvement. There is a truly great sabot design out there, waiting to be invented.

          • Curious if any 3d printing material would hold up to sabot use?

            I sketched out one a few months back to allow for a long projectile without the sabot taking up as much case capacity. But injection mold tooling is major coinye even for ‘simple’ parts.

          • ostiariusalpha

            Ehhhh… accelerating down a barrel to supersonic velocities is a rough ride, injection molding is still where it’s at for polymer sabots, sadly.

          • Is nylon still the preferred material? Wonder how something like UHMWPE of teflon infused plastic would fare.

            Or ideally, since “green” bullets seem to get funding, make them out of recycled water bottles.

          • ostiariusalpha

            I don’t know enough to say which is best, but preferably it should be the one that “plastics” the bore the least while still being at least as affordable as the LSAT/CTSAS polymer.

        • Edeco

          :S Light 243 on paper looks like it would do that.

          I’m hoping for a paradigm shift, but I’d say not as big of one as BP-smokeless was. How can I say that, if it hasn’t happened yet? There are things we could be doing to get closer right now. For instance a lot of popular, warm cartridges have short necks, which I think makes them harder on barrels.

        • jonp

          You can get there with a .30 Cal. Remington’s old Accelerator 55gr 30-06 hit 4,000fps. With new powders I’m not sure how fast you could get it but erosion would be quite a problem I would think.

  • Johannes von’ Strauch

    Sound great, and quite usefull. Though im curious to see how much it makes a diffrence in empirical therms, and if its cost efficient (for military, not private use).

  • Cyborg Fred

    Awesome! Get a barrel made from this stuff, then QPQ Nitride it and BOOM. The worlds first 5000fps service cartridge. YEAAAAAAAAAAAA!! Laser-beams n stuff!!!

    • Porty1119

      Oh, now you’ve done it…

    • PK
      • Flounder

        That ackley improved version is definitely the next gen version.

        • Some Rabbit

          I read somewhere (wikipedia?) that the highest velocity that can be achieved with smokeless powder is 5,700 fps. But to do that you’d probably need a cartridge like the one pictured and a barrel 8 feet long.

          • Major Tom

            Or a discarding sabot round.

          • Sounds like a modern varmint rig…

      • Cyborg Fred

        Kind Sir! With no body taper how is this supposed to feed in a magazine. Or are you thinking about the Top Secret (organic cage free low carbon foot print recycled polymer disintegrating/evaporating belt links) ?

    • Reef Blastbody

      Ahhhhhhh, the legendary Eargesplitten Loudenboomer.

      • J-

        Don’t bother cleaning the barrel, you have to replace it after ever box of ammo.

        • Reef Blastbody

          LOL. I’d spend the $$$ for one of those composite lined, super space age Dracos barrels, the ones with the lifetime replacement guarantee. They promise that if you shoot it out, they’ll replace it, free of charge.


        • Iggy

          Every box? Someone’s optimistic.

          • J-

            I read in Cartridges of the World that throat erosion was seen after 3 rounds and it took 15 – 20 rounds for the bullets to start to keyhole.

            Were you thinking more or less than one barrel per box?

            I wanted to try a barrel made with a rifled tungsten carbide tube press fit into a steel liner. If it works it should handle the Loudenboomer.

  • No one

    FAKE NEWS! This isn’t made in Germany therefore this steel is clearly bad.

    • Paul Prochko

      Lothar-Walther has the LW50 barrel steel that is quite a good barrel steel though it is tough to machine. I guess my question is will this new steel offer enough advantages over those such as LW50 such that there is any significant cost/benefit… However it is always nice to see new high quality steels made available… Time will tell.

  • derpmaster

    I wonder how this compares to Timken bearing steel.

  • john huscio

    Funny, i always thought famas barrels were made by beretta

    • tsubaka

      only the most modern ones (felin,G2)
      they were made to 5.56 NATO specs (as opposed to 5.56 F1)

  • DW

    Isn’t this company the one that supplies H&K?

  • English language document

    So where is this English language document?

  • Tassiebush

    This can only be a good thing

  • J-

    This drives me nuts. Somebody announces something in the gun market that had been used for years elsewhere and people treat it like it’s magic.

    In the world of metallurgy, this is called VIM VAR. It stands for Vacum Induction Melting Vacuum Arc Melting. It is a remelt process that removes sulfur and phosphorus from steel. It is a step down from powder metallurgy but PM still is difficult in large cross sections. A lot of companies do VIM VAR and market the high purity of the steel. It is a requirement in aerospace to use VIM VAR. The VIM VAR process makes an alloy go up in price about three to five times. A barrel blank in 4150 should be about $7, in this will be closer to $25. Machining will also be more difficult and add to the cost.

    The original alloy was not a gun barrel steel but was developed for Airbus for the central shaft of turbofan engines and is a aerospace grade deep hardening deep nitriding steel. It has higher chrome and lower carbon than 4140 or Mil Spec 4150 CMV. The vanadium helps with hot hardness which is why it is useful in engines and machine gun barrels. It is not used in the US because it is not an American standard alloy.

    If I were to pick an AISI steel for gun barrel use, H11 or H13 oil well drill rod would be my top choice.

    • tsh77769

      OOOOHHHH Talk dirty to me!!

    • Giolli Joker

      Is it the process that Boehler calls ESR?

      • J-

        ESR is Electro Sla Remelt. It is a variation of the VIM process but a chemical Flux called slag is added. The impurities are more solvant in the Flux than the steel and migrate into the flux. The flux is then skimmed off removing the impurities. This is very expensive and is a batch process. It is used in aerospace and nuclear grade materials to achieve the highest levels of strength.

        • jonp

          sounds not much different than the flux I add to my melt when casting bullets to remove impurities.

        • Adam D.

          On a lighter note and mostly unrelated to guns:
          a good old 13C26/14C28N or AEB-L with multi-directional rolling can still work wonders! 🙂
          As Jason Statham would put it: “nothin’ beats the classics”.

          I have to say I’m not too enamored with all the God knows how many generations of PM whiz bang nowadays, while there are still materials like 14C28N or AEB-L on the market for knives that still perform admirably for a fraction of the cost.
          Not to mention great stuff like Uddeholm’s Viking for instance,
          if re-forging capability is available.
          There are some technochilds like Nitrobe 77 I like,
          but in general I think knife steels are so overblown nowadays it’s not even funny.

          I don’t know squat about gun iron (the only material I know is S7 for some bolts, a nice shock steel for fixed blades when it comes to knives), but I guess this field is pretty similar to knife stuff as well in terms of innovation.
          Where the real progress lies with barrels in my way of thinking
          is what Proof does.
          It’s not the steel but how they’re using it.

          • J-

            I’m a fan of the Sandvik 12C27 – 14C28N steels. I have several Kershaws in that material. The Leek and (now discontinued) Piston are great. They are very clean, fine grain, vacuum processed steels that heat treat well. If you can get a Sandvik steel knife in the $40-$60 range, it is a steal.

            I do have a problem with the Southern Grind knives because it’s 14C28N for $250. My Kershaw Piston is the same size and steel for $60. For that price it should be better.

    • Thanks for the comment. I am not a metallurgist, so can be difficult for me to sort these things out.

      • J-

        I am a Ph.D. P.E. in Metallurgical Engineering. I’m happy to help sort this stuff out.

        I’m a huge knife and gun nut and have discovered that about 50% of what is out there is useful into and other 50% is voodoo and sales hokum.

        I see this with knife people all the time. Some guy will post a question like “How do you like X blade in 154CM?” and will get a response like “154CM is junk, I use S110V only. I want a knife that will cut a mile of glue back carpet and sandpaper before needing to be touched up.”

        For the overwhelming number of people a high quality vacuum remelt steel (VG-10, BD1, M690) is great. A lower end PM steel like 154CM or XHP is great too. Knives like that are easy to find in the $75-$100 range.

        You can of course buy a S90V or 204P or M390 if you want, but the majority of users won’t ever get more than bragging rights out of their blade’s performance and are going to pay $200+ for that knife.

        If you want to spend your money on that, be my guest. I have nothing against capitalism. But the lack of real metallurgical knowledge convinces some people that they need to spend WAY more than they want to or need to for the level or performance they actually need.

        • ro

          I love when the “experts” render a met engr opinion that it “crystallized and broke!”

        • Giolli Joker

          As a gun and knife nut myself, I can see where you’re coming from, I’m far from having your in depth knowledge, but I did some courses on metallurgy and I sometime get a chuckle out of some press releases…
          What I remember from one of my professors was the anecdotes like the one you mentioned about the barrels splitting… or the SCC on brass being discovered on ammunition stored too close to latrines…

      • J-

        I’ve seen the Albert & Duval literature before.

        I have an issue with the removal of sulfur from steel for gun barrels.

        Microstructure is critical. In the US resulfurized steel is used BECAUSE of its sulfur content, not in spite of it. The steel uses upwards of 0.16% sulfur and added manganese to form Manganese sulfide. This forms small stringers in the steel. Normally this is used for ease of machining, and are called free machining grade steels. There are common ones like 1118, 1137, and 1215.

        In gun barrels, the stringers add a margin of safety to the steel. Really. In case of a catastrophic failure (burst barrel) the barrel will split along the stringers. This causes the barrel to “birdcage.” It looks bad, but it is a safe situation as the barrel doesn’t turn into a pipe bomb and send shrapnel everywhere. That is the dangerous situation, pieces of barrel and chamber going flying and causing damage.

        This was discovered during WWII, somewhat by accident. When a round cooked off in British artillery pieces made with low grade steel, the soldiers had a better chance of survival. The cannon generally blew out in on one area. High grade steel barrels exploded and sent pieces flying that killed the crew. It was discovered that the sulfide controlled the fracture.

        The military spec B-11595E limits sulfur to 0.04% max.

        For machine guns I can see the value of a low sulfur, fine grain steel, but the cost is … cost. If the goverment wants to buy barrels that cost 5 to 10 times to make, they better budget for it. There is a good history with 4150 CMV in small arms. For civilians who only shoot semi auto, I doubt 99% of them would get the cost benefit of a barrel like this.

        • HSR47

          Actually, if anyone is going to benefit, it may actually be non-military users: Barrel life tends to be variable based on the firing schedule of the host firearm. Since a belt-fed MG will have a more abusive firing schedule than a manually-operated target rifle, it seems to follow that an increase in useful barrel life will be more pronounced in firearms that have less abusive firing schedules.

          • J-

            Not exactly. The mechanism of failure of small arm military barrels under sustained firing is droop. The barrel gets hot, loses stiffness and starts to deform. Once the barrel droops to a certain point, the bore becomes partially obscured and the barrel bursts. In M16/M4s with government taper barrels, this often happens right at the gas block where the barrel increases thickness again. If you look at the Albert & Duval literature link, there is an image of a FAMAS with a burst barrel.

            For civilian shooters, achieving that sustained heat load on the barrel in semi auto would be difficult to impossible. For civilian barrels the common cause of failure is throat erosion which is mostly gas cutting. The hot hardness aspect of the steel would help a little but won’t provide substantial gains against it. Going to a steel like this won’t make your 6.5-284 last twice as long.


          • Klaus Von Schmitto

            I vote that you are the steel guy around here now.

          • HSR47

            I think we got our wires crossed.

            When I referred to “useful barrel life” above, I was talking about the total number of rounds that can be fired through a barrel before accuracy declines to the point that the barrel needs to be replaced.

            Since heat accelerates barrel wear, the way a rifle is used will have an impact on the service life of the barrel installed in it: If you built two AR15 uppers using the same make/model barrel, and used one for CMP-style match shooting, and the other for 3-gun, I’d expect noticeable loss of accuracy from the 3-gun upper at a lower round count.

            I was simply suggesting that barrel alloys that are more durable and more heat resistant should stand up better than current industry standard alloys. Given that people already pay $300+ for “premium” barrels, the additional cost of newer alloys is unlikely to be a major stumbling block.

          • CavScout

            He did mention, towards the end of his comment, that when a barrel is burnt out by civilians, it’s throat erosion. That the new steel wouldn’t solve that specific problem as it wouldn’t curb that problem very much.

          • Federalist

            J- Do you have a blog, site, forum, or anything? This level of expertise shouldn’t be buried in random comments!

      • Jean Luc

        Hello Mr. Nathaniel! That is NOT a FAMAS G2. It’s a FAMAS Valorisé or VALO. Thank you

    • Bradley

      How would powder metallurgy compare as far as purity and grain structure goes?

      • J-

        Power metallurgy has among the highest purity and finest structure. It is made by mixing micro powders of the alloying elements and forging the ingot. The steel is made so the grain size doesn’t grow larger than the powder size. This creates fine steel. But the cost is in making the powder and then the ingot. It is quite expensive. High end blade steels are PM like 154CM, CTS XHP, S30V, S90V, etc.

        • ostiariusalpha

          It’s also easy enough to screw up the process. There are any number of anecdotes on the interwebs about expensive blades snapping under fairly mild flexion and getting replaced under warranty.

    • marine6680

      Good info… But do remember, not all of us are experts in that field, nor do we follow it. Many of the more knowledgeable know a good deal about matterials and alloys commonly used in firearms, like 4150 and 7075T6, but any new developments outside the firearms industry are not well know.

      I know PM simply due to my knowledge of knife steels, but the exact process is not something I am any more familiar with thanks a slightly learned layman.

      • J-

        What I do for a living is sort this stuff out for people. I don’t want to make you feel dumb, quite the opposite. I hope I can educate people so they can make more informed choices when it comes to cost/benefit analysis.

    • Mack

      So where do you stand on the C158 vs 9130 bolts in AR’s?

      Or 4140 vs 4150 barrels?

      or 6061 vs 7075 handguards and such?

  • Billy Jack

    Whoever they surrender to next will be getting some quality materials.

    • snmp

      Are you like the guys who are flee in Dunkirk in 1940

      • Billy Jack

        No. Me like guys who save you after D-Day.

        Cmon mon amie. Just a joke. I love France, the French people and their culture. France enabled my nation to be free. If people can joke that my nation is fat and retarded I can joke about France. I know that French forces regaining their form in retreat helped allow for so many to be saved at Dunkirk.

        • Eric Sebu

          We don’t see fat joke or retarded joke in any post about the US. This “joke” is unfortunaly so old and overused that many of your compatriote believe it.

          • Billy Jack

            Really? Must not be reading too closely. The very recent Slovenian Rex story has remarks about Americans not being able to find Slovenia on a map.
            The only people who believe that the French are cowards haven’t cracked a history book.
            And if you want to suggest American cowardice better to mention MacArthur fleeing the Philippines in the dark than Dunkirk which didn’t involve Americans. Seems book allergies are an international phenomenon.

          • ostiariusalpha

            Forced his men to fight when he knew they’d lose, just to make sure that his reputation was secure for not simply surrendering the Philippines. MacArthur was quite the tool.

          • Billy Jack

            In hindsight though it’s not like surviving to see the Bataan Death March or Japanese cannibalism was worth the wait. Anyway he knew the Japanese cultural view of men who surrender?

          • Tassiebush

            In the defence of New Guinea he was inattentive and dishonest.

  • John Pate

    In actual practical use, the effect will be inconsequential. Might sell in a few guns at the Gucci end of the market.

  • snmp

    Aubert & Duval is supplier of HK for French contract (HK416F)

    • Good catch! I admit the caption from the source called it a G2 and I didn’t look all that closely. I honestly spent more time making sure the image wasn’t mirrored and that it actually had the left-hand kit installed!

      • snmp

        is not Kit. in few second in FAMAS, you could switch to left side éjection :
        Open the wepon =>Rotate the bolt => Close the weapon => switch in other side the cheek peace

        • Edmond Huet

          You do not rotate the bolt, you remove the extractor and ejector after pulling the part that locks them then interchange their position before locking them again.

  • They told me explicitly that it was not ESR. The fella at the top of the comments section here seems confident that it is VIM-VAR, although the A&D reps I talked to did not use that term.

    • 10x25mm

      Aubert & Duval had both ESR and VIM-VAR remelting stations circa 2010. Probably still do. The green bordered microstructure is clearly the result of premium remelting, but it is not possible to determine which process from just this microstructure. Both ESR and VIM-VAR dramatically reduce sulphur, phosphorous, silicon, and other toughness reducing inclusions, and their light microstructures are quite similar.

      The major difference in the outcomes of the two processes is that VIM-VAR also dramatically reduces the dissolved gas (H, N, O, etc.) content of the steel, while ESR does not. The compounds formed by these dissolved gasses are usually only evident in electron micrographs.

      After reducing sulphur, phosphorous, and silicon inclusion compounds, the next available step to further improve the toughness of a high strength steel is to reduce its dissolved gas content. VIM-VAR gas reduction produces less significant increases in toughness than removing the sulphur, phosphorous, and silicon inclusion compounds alone and is often not worth the effort. VIM-VAR processing provides no advantage in reducing sulphur, phosphorous, and silicon inclusion compounds over ESR.

      VIM-VAR is a more expensive process than ESR due to the cost and time spent operating the vacuum systems, along with the smaller scale of the equipment. The Russians attempted scaling up vacuum steel processing equipment, but the additional pump down time more than offset the yield increase per cycle.

  • Nurse Ratched

    BEWARE: BrokenTengu99 . is HIV+ !!

  • Bradley

    My guess is this sort of improvement has been possible for some time with existing alloys. The steels commonly used for gun barrels are fairly simple alloys. The knife industry is using more advanced materials than most firearms use. I don’t know how the super steels used in blades would behave at a hardness appropriate for a barrel, but I’m sure there’s an alloy out there that would do the job with the right heat treatment. Another factor could be the possibility for the barrel to be much more rigid without sacrificing toughness.

  • Eric Sebu

    It’s a FAMAS Valorisé, an updated version of the FAMAS F1. G2 don’t have bipod, use the usual FAMAS handguard and can’t use the 25 round magazine specific to the other FAMAS but STANAG.

  • 22winmag

    The Rolls Royce of barrel steels.

    Do you actually know anyone who drives one?