Daniel Defense MK12 SPR — 5.56 NATO 18" (Black)

The Daniel Defense MK12 is the modern evolution of the Special Purpose Rifle (SPR) — the long-range precision platform originally developed for US special operations Designated Marksmen. Chambered in 5.56 x 45 NATO, it combines a proprietary 18" stainless steel Cold Hammer Forged barrel with exclusive MK12 profile, a Geissele SSA 2-Stage trigger, a gas block built to Crane (Naval Surface Warfare Division) specifications for USSOCOM, and the free-float DDM4 Rail 12.0 handguard. A rifle engineered for extreme precision out to 600 meters and beyond.

The SPR heritage

The SPR (Special Purpose Rifle) program was born from an operational requirement of US special forces : to field an AR-15 platform capable of delivering semi-automatic sniper-grade precision at ranges up to 600 meters, while remaining compact, modular and fast into action. The Daniel Defense MK12 carries this heritage into a premium civilian configuration, preserving the key features that made the original platform legendary : 18" long-range barrel, exclusive MK12 profile, and Crane-specification USSOCOM gas block.

An exceptional barrel

The MK12 barrel is what sets it apart from every other Daniel Defense rifle :

• Proprietary stainless steel — a specific alloy developed by Daniel Defense for precision.
• Cold Hammer Forged — hydraulic pressure forging process that produces the most accurate and longest-lasting barrels attainable.
• DLC (Diamond-Like Carbon) finish — high-performance black coating offering superior wear and corrosion resistance compared to standard mil-spec phosphate.
• MK12 profile — exclusive barrel profile engineered for the optimal balance between rigidity (precision) and controlled weight.
• 1:7" twist rate — perfect stabilization of heavy match projectiles (69 to 77 grains).
• Chamber formed during forging — ensures perfect concentricity between chamber and bore.
• HP/MPI tested — military-grade quality control.

Technical specifications

• Caliber: 5.56 x 45 NATO (.223 Rem compatible)
• Type: semi-automatic AR-15 SPR (Special Purpose Rifle) — long-range precision
• Barrel length: 18" (457 mm)
• Barrel profile: MK12 (exclusive Daniel Defense profile)
• Barrel material: proprietary stainless steel, Cold Hammer Forged
• Barrel finish: DLC (Diamond-Like Carbon)
• Twist rate: 1:7"
• Testing: HP/MPI
• Muzzle thread: 1/2 x 28 TPI
• Muzzle device: Daniel Defense Improved Flash Suppressor (17-4 PH stainless, salt bath nitrided)
• Gas system: rifle-length, direct impingement
• Gas block: MK12 Low Profile, 416 hardened stainless steel, black oxide — built to Crane (Naval Surface Warfare Division) specifications for USSOCOM
• Upper & lower: CNC 7075-T6 aluminum, Type III hard-coat anodized black, ambidextrous safety
• Lower: flared magwell, integrated rear QD point
• Upper: M4 feed ramps, indexing marks
• Handguard: Daniel Defense DDM4 Rail 12.0, free-float Picatinny quad rail, 12" (305 mm), CNC 6061-T6
• Rail panels: Daniel Defense Santoprene rail panels included (heat resistant to 300°F / 149°C)
• Trigger: Geissele SSA 2-Stage — premium precision trigger factory-fitted
• BCG: M16 profile, chrome-lined, MP tested, properly staked gas key
• Charging handle: independently ambidextrous GRIP-N-RIP
• Buffer: H buffer, 6-position mil-spec 7075-T6 tube
• Buttstock: Daniel Defense Buttstock, glass-filled polymer, soft-touch overmolding
• Pistol grip: Daniel Defense Pistol Grip, glass-filled polymer, soft-touch overmolding
• Sights: not included (continuous 1913 Picatinny rail, ready for precision optic)
• Overall length: 883 mm collapsed — 962 mm extended (34 3/4" – 37 7/8") with muzzle device
• Weight: 3.36 kg (7.41 lb) without magazine or optic
• Finish: Black (Type III hard-coat anodized upper/lower/rail, DLC black barrel)
• Made in: USA, Black Creek (Georgia)

Key benefits

• Military SPR heritage: civilian evolution of the US special forces Special Purpose Rifle platform.
• Proprietary stainless DLC barrel: unique in the Daniel Defense lineup — maximum precision and longevity.
• Crane / USSOCOM gas block: demanding military specifications applied to the civilian product.
• Factory Geissele SSA 2-Stage trigger: the world reference for AR-15 precision triggers.
• DDM4 Rail 12.0 handguard: 12" free-float Picatinny for maximum accessory mounting.
• Long-range precision: engineered to engage effectively out to 600 m and beyond with match ammunition (Mk262, 77 gr HPBT).
• Ambidextrous safety out of the box.
• Suppressor-ready precision platform.

Use cases

• Precision sport shooting: semi-auto long-range matches, distance 3-Gun, PRS gas gun class.
• Service use (Designated Marksman): platform adopted by DMs — regulated professional use.
• Precision-oriented sport shooting: steel target work 300-600 m, group testing.
• Tactical collection: iconic piece of the SPR program.
• Precision suppressor platform: 18" barrel + rifle-length gas = balanced suppressed configuration.

Recommended ammunition

To fully exploit the MK12’s precision potential (1:7" twist), favor heavy match projectiles :

• Mk262 Mod 1 (77 gr HPBT) — the historical SPR match load.
• Sierra MatchKing 77 gr HPBT — long-range match standard.
• Hornady 75 gr BTHP Match / TAP Precision.
• Nosler 69 gr HPBT Custom Competition.

What’s in the box

• 1 x Daniel Defense MK12 rifle
• 1 x Daniel Defense magazine (32 rds)
• Daniel Defense Rail Panels (Santoprene)
• 1 x Full-Latch Impact hard case
• 1 x case lock
• MK12 user manual
• HP/MPI test certificate