Sabatti’s Multi-Radial Rifling

Multi-Radial Rifling (MRR) is a special rifling type, which unlike conventional rifling doesn’t have sharp edges. This rifling is described as being made of two different alternating radiuses. Although it is not the polygonal rifling (most notably seen in Glock pistols), it is still very similar in appearance and performance.

The multi-radial rifling is pioneered by Sabatti several years ago. So it is a relatively new concept, but it seems to be gaining popularity. Sabatti offers more and more rifles with such a rifling pattern. According to Sabatti, the new rifling has a number of advantages compared to traditional ones. It results in less bore fouling and allows easier cleaning of the bore.

Unlike conventional rifling, MRR doesn’t form the distinct grooves on the bullet jacket, but rather squeezes the bullet to fill the bore geometry. The result is a better bore seal with less gas escaping past the bullet. The latter allows having around 12% more muzzle velocity. The MRR also has a better design of throat portion, where the bullet transitions into engaging the riflings. So with more velocity, less bullet deformation, and better throat geometry, the precision of the rifle also increases.

Sabatti’s MRR rifling also forms well during the cold hammer forging barrel manufacturing process.

There is another interesting statement by the manufacturer, which I’ll quote:

Shooters can improve Multi-Radial barrel performance by simply lapping the bores with abrasive paste pads with no fear of ruining the rifling edges like with traditional rifling.

Here is also a video telling about the MRR:

All the features described in the article are claimed by Sabatti and if they are correct, then this technology can be a real improvement in rifling design.

Sabatti firearms are introduced in the USA by the Italian Firearms Group.



Hrachya H

Being a lifelong firearms enthusiast, Hrachya always enjoys studying design, technology and history of guns and ammunition. His knowledge of Russian allows him to translate and make Russian/Soviet/Combloc small arms related information available for the English speaking audience.
Should you need to contact him, feel free to shoot him a message at TFBHrachyaH@gmail.com


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  • Some Guy

    So… Metford rifling then?

  • tts

    If it can be done with hammer forging then it should be fairly affordable to do right?

    • Muggo

      Yes, it could be done with cold hammer forging.
      Once the mandrel is made it doesn’t matter which type of rifling you’re making, the process of hammer forging is identical.

      • tts

        I thought for some reason polygonal rifling was significantly more expensive than standard rifling even when done with hammer forging which is why its not in common use?

        • Kelly Harbeson

          CHF is not an expensive process but it requires an expensive rotary hammer mill

          • tts

            Yeah CHF is expensive but I’ve read that for some reason doing polygonal rifling on one is even more expensive still than other rifling methods using CHF too. I have no idea why this might be true but its what I’ve seen brought up elsewhere.

          • Marcus D.

            Kahr certainly charges big bucks for it. Its C range pistols (CW, CM) are standard rifling, but its P series guns, which cost double, are polygonal rifled. Since the guns in the P series are also polymer framed and otherwise identical except for the barrel, the increased cost must relate to the barrel.

        • Bradley

          I think it might be high investment with low production cost, but I could be wrong.

  • Edeco

    The explanation isn’t working for me. What I’m seeing here looks like a realistic version of polygonal (ie with rounded corners) compared to a cartoon of polygonal, and land/groove. And vague reference to a tighter throat.

    I didn’t watch the video. Give me heck if you must. Looks like a full length infomercial, not going to try to glean hard tech info from that when it could just be gotten across with a better picture.

    • Dougscamo

      It was….the only thing missing was a studio audience clapping….

      • Edeco

        GJ taking one for the team to find out for sure

  • How exactly does this deform the bullet less? This really seems like the Mercury to polygonal rifling’s Ford (or the Opel to polygonal’s Vauxhall if you’re shooting mm instead of caliber).

  • Tassiebush

    This makes me think of Lancaster rifling. https://youtu.be/6bOy3RNyWME

  • Rnasser Rnasser

    The rifling in glocks is not poligonal, but rather rounded grooves.

  • Kelly Harbeson

    Looks similar to what the Japanese used in WWII. Different than R – style used in the AK74 but with the same claimed advantages. My experience with the CZ82 is that a lot of shooters are mistrustful of rifling they can’t see

  • Rick O’Shay

    Makes me think of the rifling on barrels made by Black Hole Weaponry.

    • Corwin Bos

      Yup, I have one, pretty damn good barrels.

      • Rick O’Shay

        Same here. I have one on my AR10. I absolutely love it.

        • E Wolfe

          As do I, on my 18″ AR. And they included a free stripped upper, so I now also own a 20″. Clever devils.

  • Ranger Rick

    Will this form of rifling result in longer barrel life?

    • Oldtrader3

      I would suspect that it will yield better barrel life with no blow by and lower specific heat?

      • Ranger Rick

        That’s what I was thinking, though throat erosion would still be an issue.

        • iksnilol

          Shorten chamber end a couple of cm and rechamber.

  • I’m going to come out with a new propellant system that uses gun cotton.

  • Mmmtacos

    That looks more like regular polygonal rifling to me, and the illustration of polygonal rifling doesn’t look like anything. Although polygonal rifling was more “hills and valleys” than anything.

    Oh and FWIW Glock rifling is kind of a hybrid of traditional Enfield and polygonal. It’s considered polygonal but has a distinct profile dissimilar to H&K or Kahr for instance (think of it as like traditional rifling but instead of a hard, square land rising it’s more like a semi-circle bump).

  • The_Champ

    All you dang kids today spoiled with your fancy “rifling”. Back in my day we would simply load a carefully rounded stone into our smooth bore aqueous to fire off at the Duke of Nemours’ heavy cavalry, and we were happy with that dangnabbit!

    • B-Sabre

      And bayonets! Who needs ’em! Just club them with the butt of your arquebus and you’re good to go!

  • tts

    Thanks yeah I’ve seen the wiki it doesn’t seem to give any of the nitty gritty details I’d like to see though.

  • Jas

    Good grief, there is nothing new under the sun. Heckler und Koch produced machineguns and pistols with this kind of rifling already in the 80s. Machinegun barrel life increased 300%. Pistols had 3% higher muzzle velocity. HK P9 had this rifling and was one of the most accurate 9mm pistols on the market. My HK P7 M13 had it. So what is so revolutionary about this one?

  • mazkact

    Kind of reminds me of the hex like bore of my 12.7mm Swedish Rolling Block. Also, the world is just now catching up to the Swedes on the 6.5 thing. Sweden figured it out in 1894.

  • uisconfruzed

    You can sell a lot when you sound that good saying it 🙂

  • User

    Ive known this Rifling for like years… why so late coverage?

  • Colonel K

    I have a cunning plan. Put matching rifling on the projectile and the bore. That should gas seal it so tightly that when it goes ka-boom, it really goes KA-BOOM! Anymore problems you want me to solve? 🙂

  • dltaylor51

    It looks like the same kind of rifling that’s in my desert eagle 44 mag,seems to work very well in my gun.

  • XRGRSF

    Ed Shilen tried this over 30 years ago, and I still have 3 bbls I purchased from him in 7mm 1 in 9 twist. The bbls gave excellent accuracy, but in order to perform they had to have a slightly tighter bore diameter. Because of this pressures tended to run high, and hand loads were required. Another issue was that they lost accuracy within 1000 to 1200 rounds. By lost accuracy I mean that they went from sub MOA to keyhole almost instantly.

    I can see where this rifling profile would work well in pistol bbls, and it obviously would be easier to manufacture by hammer forging, but I’m not convinced it will work in fast twist rifle bbls. Sabatti may have some magic that Ed Shilen didn’t have, but I think I’ll wait, and see on this one.