Daniel Defense MK18 RIII 5.56 NATO SBR 10.3” Barrel - FDE RIS III

Daniel Defense MK18 RIII 5.56 NATO SBR 10.3” Barrel - FDE RIS III

The DD4^™ MK18 RIII^™ AR15-style short-barreled rifle is unmatched in size, weight, and performance. It combines our tried-and-true MK18 with our Daniel Defense RIS III Rail Interface System. This revolutionary system takes the proven design of our two-piece RIS II rails—used by U.S. Special Operations Command (SOCOM) since 2006—and reduces weight while adding versatility by utilizing popular M-LOK attachment. So, you get the same proven free-float barrel design, durable aircraft-grade aluminum construction, and an uninterrupted upper rail platform with Mil-Spec 1913 rail of the RIS II—plus seven M-LOK attachment points along the handguard and integral QD swivel attachment points on both sides!

The rest is all MK18, including a 10.3-inch Cold Hammer Forged barrel—the same length found in the MK18 upper most commonly used for CQB operations. An independently ambidextrous GRIP-N-RIP Charging Handle accommodates left- and right-handed shooters, and the rifle comes with our ergonomic Daniel Defense Buttstock and Pistol Grip as well as three (3) low-profile rail ladders made from heat-resistant Santoprene to protect your support hand.  

RIS III M‑LOK Rail System
Lightweight evolution of the SOCOM‑proven RIS II with seven M‑LOK slots and integral QD points.

10.3" Cold Hammer Forged Barrel
Government‑profile, chrome‑lined barrel built for extreme durability and CQB accuracy.

Ambidextrous GRIP‑N‑RIP Charging Handle
Fully ambidextrous design supports left‑ and right‑handed shooters.

Free‑Float Barrel Design
Enhances accuracy and consistency under sustained fire.

Aircraft‑Grade Aluminum Receivers
CNC‑machined 7075‑T6 upper and lower with Type III hard‑coat anodizing.

Daniel Defense Furniture
Ergonomic buttstock and pistol grip with soft‑touch overmolding for superior control.

Low‑Profile Gas Block
Pinned 4140 steel block ensures long‑term reliability in demanding conditions.

Made in the USA
Built to the highest standards of quality and craftsmanship.

Specifications

• Caliber: 5.56mm NATO
• Barrel Length: 10.3"
• Barrel Profile: Government
• Barrel Material: Chrome Moly Vanadium steel
• Barrel Treatment: Cold Hammer Forged, chrome lined, heavy phosphate coated
• Twist Rate: 1:7
• Gas System: Carbine‑length direct impingement
• Gas Block: Pinned low‑profile 4140 hardened steel
• Muzzle Device: Daniel Defense flash suppressor, 17‑4 PH stainless steel, nitride finished
• Upper Receiver: 7075‑T6 aluminum, Type III hard‑coat anodized
• Lower Receiver: 7075‑T6 aluminum, flared magwell, QD point, Type III hard‑coat anodized
• Handguard: 9.5" RIS III, 6061‑T6 aluminum, Type III hard‑coat anodized
• Bolt Carrier Group: M16 profile, chrome lined, MP tested, properly staked gas key
• Charging Handle: GRIP‑N‑RIP ambidextrous
• Receiver Extension: 6‑position Mil‑Spec 7075‑T6 aluminum
• Buttstock: Daniel Defense polymer with soft‑touch overmolding
• Pistol Grip: Daniel Defense polymer with soft‑touch overmolding
• Rail Ladders: Three Santoprene ladders, heat‑resistant to 300°F
• Overall Length: 26 3/4" – 29 7/8" (with muzzle device)
• Product Weight: 5.73 lbs
• Muzzle Thread: 1/2 × 28 TPI
• Magazine: DD 32 Rd magazine included