Ian, Karl Talk Barrels with Nathan From Faxon Firearms

We rarely get to pick the brains of the people in our industry who are the technical geniuses that bring the products we love and enjoy to fruition. In this episode of InRange TV, Ian and Karl from Forgotten Weapons have a candid Skype talk with Nathan from Faxon Firearms about various barrel making procedures. They specifically discussed the differences between Nitride and chrome lined barrel manufacturing that takes place at Faxon. Although from the outset, Nitride might seem to be of lesser quality than a chrome lined barrel because it is cheaper but really this has to do with the manufacturing process involved. Nitride is used to treat the actual bore while chrome lining is a lining that has to be inlaid into the barrel, and thus could see more imperfections over time.

But the advantages of chrome lining are that it provides great protection against corrosive ammunition which was a very large issue in the previous century. Something I didn’t realize is that the Japanese military was the first large-scale military to adopt chrome lined barrels with the Type 99 Arisaka. Another advantage of chrome lined barrels is in machine guns in service with the military because of the heat transfer capabilities of being chrome lined.

Make sure you give the video a watch as it discusses a number of subjects in a very candid way that we rarely get. The only point of improvement I would say is that if the audio were better, it would be a much easier to follow the dialogue.





Miles

Infantry Marine, based in the Midwest. Specifically interested in small arms history, development, and usage within the MENA region and Central Asia. To that end, I run Silah Report, a website dedicated to analyzing small arms history and news out of MENA and Central Asia.

Please feel free to get in touch with me about something I can add to a post, an error I’ve made, or if you just want to talk guns. I can be reached at miles@tfb.tv


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  • Tyler McCommon

    I’m sure no one has seen this at all. No one.

  • MPWS

    From my residual knowledge from industry I keep, I remember that “cold-hammer-forging” is relatively most problem prone. Fro one it requires the most expensive type of steel, such as 4340, specially formulated. The manufacture learning curve is long and costly in terms of scrap produced. Consider 3-d re-forming (if includes longitudinal flow) of material under waves of impacts. Material is resisting and does not flow always equally as you want. That creates ‘folds’ known as striations. Those are potential source of corrosion start-up (unless covered by chrome) and potential stress risers.

    The gentleman in interview covered well for all other methods.

    • ostiariusalpha

      4140 and 4150 steels get used far more often for CHF barrels than 4340.

    • OnWardandUpward

      Don’t use poor-quality bar-stock as your blank and you will not encounter any striations. Generally, impurities and inclusions, when encountering the hammers, induce striations. FWIW.

  • SomeRandomGuy

    Hammer Forged barrels are far denser (see: more massive per cubic cm) and exhibit a vastly improved harmonic stiffness throughout heating and cooling processes. If you’re CHF barrel “walks” on you, it was not made properly. In regards to stress-relieving, if the hammer-forging process is uniform (which most respectable barrel makers tend to be: CZ, Steyr, HK, FN, DD, etc.), the stress applied will be uniform. Bear in mind it will be longitudinal (directional) stress–which should read directionally tempered or work-hardened–assuming the mandrel is true and the hammers are indexed correctly. CHF barrels tend to have far greater harmonic density (i.e. stiffness) due to their denser structure.

    As someone who used to make button-rifled barrels for a living, they do have their advantages…for certain functions. But to say that a hammer-forged barrel will “walk” more upon heating than a button/broach-cut or acid-etched is abjectly false and totally irresponsible.

    Part of his explanation of the CHF “walking” issue was that when it was shot and heated up, it would be stress-relieved from that and thus causing the walking…not a minute after claiming there was no way to effectively stress-relieve a CMF barrel.

    This was a good interview and Nathan knows his trade, I’m not taking any of that away from him. I just wanted to nit-pick this part, as someone who has done T&E for all kinds of barrels and was formerly involved in a precision button-rifle manufacturer. CHF barrels have their function, Button and Broach and Acid-Etch have theirs (though Acid-etch tends to mostly be in revolvers).

    • Colonel K

      I noticed that, too. I imagine if he’d had a chance to review his own comments, he might have edited them a bit. It’s tough to speak on the fly without making mistakes, so I’ give him the benefit of the doubt. Thirty years ago I was building match ARs using broach cut heavy barrels because they were considered superior to button rifling. Flutes were coming into vogue, so I tried them, but with poor results. Stringing or inexplicable flyers were common in any five-shot group, no matter what loads we developed. This drove me back to using heavy untapered barrels. About that same time cryogenic freezing was introduced to stress relive barrels. I never tried it, and don’t see it mentioned anymore. Anybody know why? I still believe short, fat barrels give better consistency than long barrels, and with today’s powders the loss of velocity is not such a big issue.

      • Indeed. Heavy barrels will always be better than fluting for reasons mentioned for extreme precision. Fluting is a balance to reduction in weight and increase in surface area compared to absolute precision.

        • Colonel K

          Thanks Nathan. A client just asked me to build him a precision AR carbine, so I’m checking out your barrels to see if one of them will fit his needs.

    • noob

      I saw a hammer forging video on youtube that I unfortunately didn’t bookmark where these guys had to remove the hammers from the CHF machine every 1000 barrels or so and this old guy with glasses and a probe would measure their dimensions at 22 points on six critical surfaces and then true them up with a hand file. Crazy stuff.

  • Polaritypictures Ken

    vid’s a week old, nice you guys stay attentive and up to date.

  • Bradley

    I’m pretty sure nitride treatment is significantly more corrosion resistant than chrome. I could be wrong but you might want to look into it for your own information.

  • DwnRange

    Faxon barrel (ultra-lite) user and believer here – great information and a quality product in my book, nothing beats a lightweight (7#ish AR w/ fully loaded 20 rnd mag, BUIS, T1 and TLR1s light) that shoots 77grn smks great too.

  • Colonel K

    That must be one big bore to fit the EDM/ECM equipment inside of. I
    wonder if 3-D printing will ever be able to match it for strength.
    Perfect, stress-free bores really take away the alibis.

  • noob

    Stellite All The Things!

    it might be interesting to have precision EDM Stellite trigger groups for wear resistance on the auto sear in machine guns.