Newtown Firearms’ Infinitely Adjustable Gas Piston System

Tagged with a name that reminds me of continuously variable automobile transmissions, Newtown Firearms of Siler City, North Carolina have announced an “infinitely adjustable” gas piston operating system:

Siler City, N.C. – Following their move from Placerville, Cal. to Siler City, N.C., Newtown Firearms has launched the NF-15 S.M.A.A.R.T. System (Superior. Modular. Adjustable. Automatic. Rifle. Technology.), an infinitely adjustable gas piston system for use in all AR-15 platforms.
With 48-position tuning capabilities, the NF-15 S.M.A.A.R.T. System allows shooters to make adjustments not only for atmospheric conditions but for variances across ammunition suppliers. Using the 48-position adjustable knob, shooters can easily make on-the-fly adjustments to any pressure level within the AR-15 platform producing minimum felt recoil that allows for faster target acquisition while at the same time maintaining all of the typical benefits of a piston driven system, including cooler operating temperatures and easier cleaning.
Newtown Firearms NF-15 S.M.A.A.R.T. System comes with a Nitromet coating and is compatible in all AR-15 platforms with a medium contour .750 barrel. An upgraded physical vapor deposition (PVD) or diamond-like carbon (DLC) coating is available for those that desire ultimate friction reduction at even lower operating temperatures while increasing the overall performance and lifespan of the NF-15 S.M.A.A.R.T. System.
NF-15 S.M.A.A.R.T. System
  • Universal gas piston system with one-piece carrier
  • Infinitely adjustable to any pressure level
  • 48-position adjustable knob
  • Available in Nitromet, PVD or DLC coatings
  • Patent No: US 8869674
The NF-15 S.M.A.A.R.T. System is available through Country Arms, a division of Newtown Firearms, and may be purchased separately or as part of a complete AR-15 rifle by calling (919) 663-0864 or online at

Newtown Firearms AR-15 with SMAART gas system.


The title image makes it pretty clear how the system works: The regulator has a tapered extension, and is threaded. As the regulator is screwed in, the tapered segment increasingly interrupts the flow of gas to the short-stroke piston, while a simple spring clip keeps the regulator in position.

48 positions seems excessive for a gas regulator, though it is possible Newtown Firearms had a specific problem in mind when they designed the SMAART system.

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


  • Raven


  • Esh325

    If there aren’t already enough op rod conversions on the market, but a 48 position gas regulator? Ridiculous.

  • Dan

    If only they had made it a 50 position, holy hell I am going to install a motor on it so I can adjust it remotely. With presets for know ammo. Wait, no no I am not.

  • TangledThorns


  • Sam Schifo

    And here I am with my Adams Arms with only three positions.

  • Patrick Mingle

    eeeeesh Newtown Firearms? They must have a hell of a PR department to have a name like that nowadays

    • Kurt Akemann

      Indeed. It’s like they’re handing Sarah Brady the cane with which she’ll flog them.

  • David

    Quite Possibly the worst name for a gun company that I could imagine.

  • Isaac Newton

    The “infinite detents” reminds me of the FAL gas block a little.

  • JSmath

    It’s probably marketing/product naming to get people’s attention.

  • JSmath

    Those 48 positions are definitely going to bite the reviews of this right in the butt. For fine tuning a weapon for a specific ammo, it would be great.

    Being able to adjust something based on tactile experience goes out the door when you have that many positions, though. You might be able to memorize “12 clicks up or down” to go from high velocity to subsonic ammo and back, but what if you bump into or rub against something and it clicks off a few? Leave it to guessing? Or if someone else changes the setting when you don’t have possession of the weapon? Gotta go all the way back to position 1 or 48, then manually click those dozens of positions to get somewhere in the middle ~~ Not going to be fun for the owners.

    7-12 positions, even if it involved a lot of free swing (180-360 degrees) between locks would have been much better, imo.

  • Sledgecrowbar

    Seems like the marketing department took one too many Vicodins. Excessive acronymization with questionable adherence to acceptable standards, even the already-questionable status quo for acronymization that we put up with. And knowing infinitely more about exploiting buzzwords than what “infinite” actually means.

    I want to like it, it seems to be an evolution of existing kits which is not a bad thing. Finer adjustment is not a disadvantage for most use, and even for folks who just want two settings, one for normal operation and one for suppressed, finer adjustment offers better operation at both settings, the only downside is that you have to count more clicks every time you switch. I don’t know who needs to be able to switch from normal to suppressed or back so quickly that this is a real downside, outside of two-way range theater.

    Why no Nickel Boron? And how will the street price compare to existing systems?

    I think I’m one of the handful of people who have an Osprey kit (and actually made it fit under a freefloat rail). It’s supposed to be self-regulating, but the advantage that I can choose my own gas block allowed me this kind of adjustment plus one more part of customization (or standardization). That said, I’d like to see a kit like that, basically just a replacement for the gas tube and bolt carrier, that fits under a reasonable majority of handguards. The practice of bundling it with a proprietary gas block is of questionable advantage.

    • Ergo

      I picked up an osprey on a black friday sale. I’m guessing me and the three other people with them are interested in what rail you fit it under and what mods had to be done to it.

  • rollen

    I have a di upper from these folks when they were still here in gold country. Love it and shoots 2.5 moa with a loop sling in prone. Rob (the owner) was a big time FAL guy and yeah that’s where the idea came from, never shot this setup so I can’t speak to the quality or function. I can say when they were local they ran a stand up business and were good people. It’s unfortunate that they had their shop out Newtown road where the old gold camp of the same name was. California is not kind to businesses in the gun industry and they had connections in NC. If you look up the shop it goes by country arms now.. I wish them the best of luck.

  • Gunhead

    Having been to their shop when they were still in Placerville, I can say I was a lot less interested in the $7000 NF-15 than in what must have been one of very few SPAS-12s in California…

  • gunslinger

    looks like the company started in 2003, in Newtown CA. then moved to NC.

    not sure if the events of 2012 caused a change…

  • uisconfruzed

    Another reason for me to pay a visit to Siler City now.

  • DetroitMan

    I can see something like this for a match gun, where you can tailor to a specific load and dial out as much recoil as possible. But for a working gun, less is more. Three or four positions plus an “off” position should be the max.