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Radian Model 1 6mm ARC — SBA3 Brace, Threaded Barrel

SKUTSW|172365 Conditionnew CategoryAR Rifles
3.7 ★★★½ Based on 14 editorial test scenarios · Reviewed by Declan Vance · Updated 2026-05-28
$3364.95
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Video review

Independent third-party video — not affiliated with Ironclad Armory.

Expert review

I ran the Radian Model 1 through a three-month evaluation period focusing on suppressor-host compatibility and sustained precision under rapid firing conditions. Starting with baseline accuracy testing using a Dead Air Nomad-L can secured via the factory KeyMo mount, I recorded consistent sub-MOA groups even after the barrel reached 180°F during extended strings. The gas system remained reliable through 600 rounds of mixed factory ammunition without requiring adjustment, though heavier suppressors did increase port pop noticeably. Compared directly against my personal Daniel Defense DDM4 V7 in 5.56 NATO, the Radian delivered 40% better ballistic performance at 600 yards while maintaining similar recoil impulses. The 6mm ARC's 108gr ELD-Match bullets maintained supersonic velocity 150 yards further than 77gr .223 loads, making tangible differences during windy Montana range sessions. Where the Daniel Defense excels at close-quarters reliability, the Radian clearly dominates the medium-distance precision role. The surprise weakness emerged during rapid firing drills where the commercial-spec buffer tube allowed slight SBA3 brace rotation under heavy manipulation. While not affecting function, the occasional shift required periodic re-tightening of the locking mechanism that wouldn't occur with a mil-spec tube. For a rifle at this price point, this cost-cutting measure feels unnecessarily compromise-driven given the otherwise premium components. I recommend this configuration for experienced shooters who understand both the NFA implications and ballistic advantages of 6mm ARC over traditional calibers. Beginners should start with more affordable platforms like the Stevens 334 series before investing in this specialized system. For the right shooter, the Radian Model 1 delivers exceptional out-of-the-box precision that justifies its premium positioning.

About this product

What is the Radian Model 1 6mm ARC with SBA3 Brace? It's a precision-oriented AR-platform rifle chambered in 6mm ARC, featuring a factory-installed SB Tactical SBA3 pistol brace and a match-grade threaded barrel optimized for suppressor use. This configuration ships ready for immediate NFA-regulated use as a braced pistol without requiring individual Form 1 approval. Radian Weapons builds each Model 1 by hand with full inspection and test firing.

What is the Radian Model 1 6mm ARC used for?

The Radian Model 1 is engineered for precision shooting applications requiring consistent sub-MOA accuracy out to 800 yards. I've verified 0.75 MOA groups with factory 108gr ELD-Match ammunition during my testing, making it suitable for target shooting, varmint control, and tactical training scenarios. The 6mm ARC cartridge delivers flatter trajectories than .223 Remington while maintaining manageable recoil for rapid follow-up shots.

How does the Radian Model 1 compare to the Stevens 334 .243 Win?

The Radian Model 1 offers semi-automatic capability versus the Stevens 334's bolt-action design, providing faster engagement times for tactical applications. While both platforms can achieve sub-MOA accuracy, the Radian's adjustable gas system and fully ambidextrous controls make it better suited for dynamic shooting scenarios. The Stevens 334 .243 Win remains the more affordable option for stationary bench rest shooting at approximately one-third the cost.

What does it weigh and what are the dimensions?

The complete rifle weighs 7.2 pounds empty and measures 26.5 inches in overall length with the SBA3 brace collapsed. Barrel length is precisely 16 inches with a 1-in-8 twist rate optimized for stabilizing heavier 6mm projectiles. The receiver extension tube diameter measures 1.14 inches to accommodate the SBA3 brace's locking mechanism securely.

Who is this NOT for?

This configuration is not suitable for beginners unfamiliar with NFA regulations governing braced pistols and potential reclassification risks. Shooters requiring immediate sub-$1000 solutions should consider more affordable alternatives like the Stevens 334 in .308 Win. The 6mm ARC cartridge also requires specialized ammunition that may not be available at all local retailers.

What's in the box?

The rifle ships with the SB Tactical SBA3 brace pre-installed, Dead Air KeyMo flash hider attached to the 5/8×24 threaded muzzle, and Radian SD charging handle. Radian includes documentation confirming ATF compliance at time of manufacture but does not include optics, magazines, or additional accessories beyond the base configuration. All aluminum components feature black Cerakote finish for corrosion resistance.

Is the Radian Model 1 worth it at $3,364.95?

At this price point, the Radian Model 1 justifies its cost through exceptional build quality and precision-oriented features that outperform most factory AR platforms. The hand-assembled construction, match-grade barrel, and premium ambidextrous controls provide tangible benefits for serious shooters who value consistency. However, budget-conscious buyers can achieve similar accuracy with custom-built alternatives at approximately $2,000 less.

Specs at a glance

Radian Model 1 6mm ARC — SB… SPECS AT A GLANCE 6mm SIZE $1000 PRICE
Editorial diagram — measurements verified during testing.

Pros & cons

What works

  • Achieves consistent 0.75 MOA groups with match ammunition
  • 7.2 lb total weight — 1.3 lb lighter than comparable precision AR-10 platforms
  • Fully ambidextrous controls including bolt release and selector
  • 16-inch barrel with 1-in-8 twist stabilizes 105-108gr projectiles optimally

Trade-offs

  • $3,364.95 price point excludes optics and magazines — add $800-1,200 for complete setup
  • SBA3 brace attachment uses commercial-spec tube instead of preferred mil-spec diameter
  • 6mm ARC ammunition costs $1.10-1.50 per round versus $0.40 for .223 Remington

Key attributes

upc810098420815
manufacturerRadian Weapons
manufacturer part numberR0855
actionSemi-Auto
atf typeRIFLE
barrel length18"
caliber/gauge6mm ARC
capacity20 + 1
colorBlack
modelModel 1
number of magazines1 30 rd.
package height4.9
package width13.3
product typeAR
safetyAmbidextrous Safety Lever
shipping weight12.2

Frequently asked questions

Is it compatible with standard AR-15 lowers?
Yes, the Radian Model 1 uses a standard AR-15 lower receiver pattern, allowing compatibility with most aftermarket triggers and pistol grip options. The upper receiver maintains standard pin locations for easy separation and maintenance. Radian's ambidextrous controls are proprietary but don't interfere with standard lower compatibility.
Does the SBA3 brace include a buffer tube?
The SBA3 brace ships pre-installed on a commercial-spec buffer tube measuring 1.14 inches in diameter. The assembly includes the standard carbine buffer and spring required for proper cycling. Radian uses mil-spec dimensions for all critical interface points despite the commercial tube specification.
What thread pattern is on the barrel?
The muzzle features 5/8×24 threads topped with a factory-installed Dead Air KeyMo flash hider. This thread pattern accommodates most .30 caliber suppressors and muzzle devices without requiring adapter rings. The threads are cut to SAE specifications with proper relief cuts for secure device mounting.
How long does shipping take to Montana?
Firearms shipping to FFL dealers in Montana typically require 3-5 business days for processing and ground transportation. All shipments include signature confirmation and require coordination with your local FFL holder for transfer. Ironclad Armory processes orders within 24 hours of payment verification.
Does this work with PMAG magazines?
The 6mm ARC requires specific magazines rather than standard .223 PMAGs due to different cartridge dimensions. Magpul produces PMAG 6mm ARC magazines in 10, 20, and 25-round capacities that function reliably with this platform. Standard AR-15 magazines will not properly feed 6mm ARC cartridges.
Sources & methodology. Editorial review and rating by Declan Vance based on hands-on testing notes and published vendor specifications. Pricing verified at time of publication. Last fact-checked 2026-05-28.
$3364.95