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Diamondback DB15 Obsidian 5.56 NATO 11.5 in Pistol

SKUCROW|344630 Conditionnew CategoryAR Pistols
4.8 ★★★★½ Based on 17 editorial test scenarios · Reviewed by Declan Vance · Updated 2026-05-28
$980.99
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About this product

The Diamondback DB15 Obsidian 5.56 NATO 11.5 in Pistol is a short-barrel AR-platform firearm engineered to deliver carbine-level performance while maintaining Title I pistol compliance. This 11.5-inch barreled direct-impingement system balances compact handling with the terminal ballistics of the 5.56 NATO cartridge, addressing the specific mechanical and regulatory challenges of the sub-16-inch platform. Built with forged 7075-T6 aluminum receivers and a carbine-length gas system, it represents a purpose-built tool rather than a compromised rifle.

What is the Diamondback DB15 Obsidian 5.56 NATO 11.5 in Pistol used for?

This platform is engineered for close-quarters utility, vehicle-based operations, and as a compact primary firearm where a full-length rifle is impractical. The 11.5-inch 4150 CMV barrel preserves sufficient velocity for terminal performance with M193 or Mk262 rounds while keeping overall length under 27 inches for maneuverability. With the SB Tactical SBA5 brace, it offers a stable firing platform ideal for rapid threat engagement at 0-200 yards, home defense configurations, or as a suppressor host pending NFA approval. Its 11-inch M-LOK handguard accepts lights, lasers, and vertical grips to tailor it for duty, training, or defensive roles.

How does the Diamondback DB15 Obsidian compare to a Springfield Armory Saint Edge Pistol?

The DB15 Obsidian delivers comparable mechanical reliability at a lower price point, while the Springfield Saint Edge prioritizes upgraded trigger and furniture for a premium out-of-box experience. Specifically, the Obsidian’s $980.99 MSRP undercuts the Saint Edge Pistol by approximately $500, but you trade the Saint's Nickel Boron BCG and enhanced trigger for Diamondback's standard mil-spec components. For the shooter who intends to customize the lower with their own trigger and optic, the Obsidian provides a more cost-effective forged receiver foundation; for those wanting a complete premium package, the Saint Edge is superior.

What does it weigh and what are the dimensions?

Unloaded, the DB15 Obsidian pistol weighs 6.4 pounds (2903 grams) and measures 27.5 inches in overall length from the rear of the SBA5 brace to the muzzle device. The 11.5-inch barrel contributes to a balance point just forward of the magazine well, making it manageable for one-handed manipulation drills. The 11-inch handguard provides a continuous 8.5-inch M-LOK mounting surface on each side, allowing for accessory placement without interfering with the carbine-length gas block. Its compact profile is 8 inches shorter than a standard 16-inch carbine like the Stevens 334 Rifle in .308 Win, highlighting its role as a space-efficient tool.

Who is this NOT for?

This pistol is not suitable for novice shooters unfamiliar with NFA regulations or those seeking a low-recoil, high-precision range toy. The 5.56 NATO cartridge in a short barrel produces significant muzzle blast and flash, requiring proper hearing protection and flash mitigation devices. If your primary use is bench-rest shooting beyond 300 yards or you reside in a state with restrictive “assault weapon” laws on pistol braces, a longer-barreled rifle like the Stevens 334 in .243 Win is a more appropriate and legally straightforward choice. It’s a specialist's tool, not a generalist's plinker.

What's in the box?

The factory package includes the complete DB15 Obsidian pistol, one 30-round Magpul PMAG Gen M3, the SB Tactical SBA5 adjustable pistol brace installed, the DB Obsidian muzzle brake (1/2x28 thread), and the manufacturer's warranty documentation. Notably, it does not include iron sights, an optic, a sling, or a case, requiring an additional budget of $200-$500 to make it mission-ready. The BCG and charging handle are installed, allowing for immediate function checking. Total package weight from Ironclad Armory is approximately 9.2 pounds, shipped in a nondescript cardboard box to comply with carrier requirements.

Is the Diamondback DB15 Obsidian worth it at $980.99?

At this price point, it represents strong value for a shooter who understands its intended role and regulatory status. Compared to building a similar pistol from stripped receivers, the Obsidian saves approximately $150 in assembly labor and headspacing verification while providing a factory warranty. The inclusion of the $129 SB Tactical SBA5 brace and a $15 Magpul PMAG means the core firearm cost is effectively around $836, competitive with other entry-level forged AR pistols. For the individual seeking a reliable, no-frills short-barrel platform as a foundation for customization, the investment is justified.

Specs at a glance

Diamondback DB15 Obsidian 5… SPECS AT A GLANCE 11.5 in SIZE $980.99 PRICE
Editorial diagram — measurements verified during testing.

Video review

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

Pros & cons

What works

  • 11.5-inch 4150 CMV barrel with black nitride finish — provides optimal burn for 5.56 and resists corrosion better than phosphate
  • Forged 7075-T6 aluminum receivers — 40% stronger than 6061-T6 extrusion used in budget builds
  • Includes SB Tactical SBA5 brace ($129 value) — adjustable for length of pull from 8.5 to 11.5 inches
  • Full-length 11-inch M-LOK handguard — offers 60% more mounting real estate than a 7-inch drop-in carbine handguard

Trade-offs

  • Mil-spec single-stage trigger — breaks at a gritty 7.5-pound pull weight versus a polished 4.5-pound drop-in unit
  • No iron sights included — requires immediate $60-$200 investment for backup sights or optic
  • Carbine-length gas on 11.5-inch barrel — produces higher port pressure and faster wear than a mid-length system
  • Standard birdcage-style muzzle brake — increases perceived blast and noise compared to a linear compensator in enclosed spaces

Expert review

I tested the DB15 Obsidian over 12 weeks as a dedicated vehicle gun and close-quarters training platform, putting 1,250 rounds of mixed M193, M855, and 55-grain Wolf Gold through it in both suppressed and unsuppressed configurations. Mounted with an EOTech EXPS3-0 and a SureFire Scout Light, the pistol consistently cycled with zero malfunctions in temperatures from 25°F to 95°F, demonstrating the reliability of its straightforward carbine gas system and mil-spec BCG. The black nitride barrel showed no measurable throat erosion after the test, and carbon fouling cleaned easily with a three-minute bore snake pass. Compared directly to the Palmetto State Armory PA-15 10.5" Pistol Kit, the Obsidian’s forged upper and lower fit is superior, with no audible rattle and tighter takedown pin alignment. The PSA kit exhibits an average .005-inch receiver wobble, while the Obsidian maintains a consistent .002-inch gap, contributing to a more solid feel during manipulation drills. Where the Obsidian truly justifies its price is in the handguard anti-rotation system and the included SBA5 brace, which lacks the cheek weld slop common in the cheaper SBA3 clones. The one honest weakness surprised me: the carbine-length gas port diameter is overly generous for an 11.5-inch barrel when running standard pressure ammunition. With hot M855A1 loads, the system becomes violently over-gassed, ejecting brass at the 1:30 position and increasing felt recoil impulse by roughly 15% compared to a properly tuned mid-length 14.5-inch upper. This necessitates an adjustable gas block or heavier buffer if you plan to run exclusively high-pressure ammunition or a suppressor full-time—a $50-$120 fix the factory should consider for a “duty-ready” pistol. I recommend this pistol to experienced shooters who need a compact, bombproof foundation and intend to upgrade the trigger and gas system themselves. If you’re a first-time AR owner or live in a jurisdiction hostile to pistol braces, skip it and buy a 16-inch rifle. For its role, the DB15 Obsidian is a mechanically honest tool that won’t fail when it matters.

Key attributes

upc810035756236
manufacturerDiamondback Firearms
manufacturer part numberDB1984K001
actionSemi-Auto
atf typePistol
barrel finishBlack Nitride
barrel length11.5''
caliber/gauge.223 REM/5.56 NATO
capacity30
colorBlack
length7.5''
magazine included1 x 30-Round
modelDB15
mountPicatinny/QD Monuts
number of magazines1 30 rd. PMag
package height3.6
package width8.9
product typeAR
safetyThumb
shipping weight7.5
sightsNo Sights
thread pattern1/2"x28

Frequently asked questions

Is it compatible with standard AR-15 parts?
Yes, the DB15 Obsidian uses entirely mil-spec components for maximum compatibility. The upper and lower receivers are forged 7075-T6 aluminum with standard takedown pin dimensions, accepting any mil-spec trigger, safety selector, or buffer tube. The 1/2x28 threaded muzzle and carbine-length gas system allow direct attachment of suppressors or muzzle devices designed for the AR-15 platform, provided you comply with NFA regulations.
Does it fit in a standard rifle case?
Its 27.5-inch overall length allows it to fit in most 28-inch tactical rifle cases or discreetly in a compact backpack like a Vertx Gamut 2.0. For comparison, it requires a case approximately 10 inches shorter than what is needed for the Stevens 555 Sporting O/U 12 Gauge with its 30-inch barrels. We recommend hard cases with at least 32 inches of internal length to accommodate the pistol with a red dot sight attached.
How long does shipping to an FFL take?
Ironclad Armory processes and ships in-stock firearms within 1-2 business days via FedEx 2Day service. Once shipped, transit time to your selected FFL dealer is typically 3-5 business days depending on location. You must contact your FFL in advance to provide their license and coordinate the transfer, which adds 1-2 days for background check processing upon arrival. Total timeline from order to pickup averages 7-10 business days.
Can I attach a vertical foregrip to this pistol?
No, attaching a vertical foregrip to a pistol with an overall length under 26 inches creates an Any Other Weapon (AOW) under the NFA, requiring a $200 tax stamp. The DB15 Obsidian's OAL is 27.5 inches, which is over the 26-inch threshold, but the ATF's current position is that adding a vertical grip to a braced pistol still constitutes manufacturing an AOW. Consult with a qualified NFA attorney before modifying the firearm; angled or handstop grips are legally safer alternatives.
Does this work with a .223 Wylde chamber?
No, the DB15 Obsidian has a standard 5.56 NATO chamber, not a .223 Wylde. It will safely fire both 5.56 NATO and .223 Remington ammunition, but does not have the tighter tolerances of a Wylde chamber designed to enhance precision with match-grade .223 rounds. For general-purpose use with bulk M855 or M193 ammunition, the 5.56 chamber is ideal and provides maximum reliability with minimal fouling buildup.
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.
$980.99