Daniel Defense MK18 Upper Receiver Group
Iconic 10.3" 5.56 NATO URG with RIS II quad rail, the same configuration used by USSOCOM.
- Price
- $1,641
- Weight
- 3 lb 8 oz
- Brand
- Daniel Defense
- Category
- Uppers
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Features
- •5.56 NATO
- •10.3" CHF barrel
- •Carbine gas
- •RIS II quad rail
- •BCG & GRIP-N-RIP CH included
Capability Boosts
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Price History
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Guides
Overview
The Daniel Defense MK18 Upper Receiver Group is the commercial version of the upper receiver used by US Special Operations Command (USSOCOM). Built around a 10.3" cold hammer forged barrel, the MK18 configuration has been battle-proven in conflicts worldwide and remains the gold standard for close-quarters battle rifles.
The defining feature is the RIS II (Rail Interface System II) quad rail handguard, which has been rigorously tested by USSOCOM and adopted for the Block II SOPMOD program. The RIS II features Daniel Defense's bolt-up mounting system for rock-solid attachment, with Picatinny rails at the 12, 3, 6, and 9 o'clock positions. Included Santoprene rail panels (heat-resistant to 300°F) provide grip and protection when rails are not in use.
Every MK18 URG ships complete with an M16 profile bolt carrier group (MPI tested, chrome lined) and the GRIP-N-RIP ambidextrous charging handle. The 1:7 twist barrel stabilizes both 55gr and 77gr projectiles, maximizing the versatility of the 5.56 NATO cartridge in a compact package.
Key Features
- Cold hammer forged 10.3" barrel, chrome lined, HP/MPI tested
- RIS II quad rail handguard (USSOCOM-tested bolt-up system)
- Santoprene rail panels included (heat-resistant to 300°F)
- M16 profile BCG, MPI tested with properly staked gas key
- GRIP-N-RIP ambidextrous charging handle
- 7075-T6 aluminum upper receiver with M4 feed ramps
- Daniel Defense flash suppressor
Pros
- +Battle-proven configuration used by USSOCOM
- +RIS II provides maximum accessory mounting flexibility
- +Compact 10.3" barrel ideal for CQB and vehicle operations
- +Complete package with BCG and charging handle
- +Rail panels protect hands and provide grip texture
- +Daniel Defense lifetime warranty
Cons
- −Premium pricing
- −Quad rail heavier than M-LOK alternatives
- −10.3" barrel requires SBR registration or pistol build
- −Increased muzzle flash and blast in 5.56 NATO
- −Rail panels add bulk compared to M-LOK systems
Detailed Specifications
- caliber
- 5.56mm NATO
- barrelLength
- 10.3"
- barrelProfile
- Government
- barrelMaterial
- Chrome Moly Vanadium Steel, Cold Hammer Forged
- barrelFinish
- Chrome Lined, Mil-Spec Heavy Phosphate
- twist
- 1:7
- gasSystem
- Carbine Length, Direct Impingement
- gasBlock
- Pinned Low Profile, 4140 Steel, Phosphate
- handguard
- RIS II MK18, 6061-T6 Aluminum, Quad Rail
- upperReceiver
- 7075-T6 Aluminum, Type III Hard Coat Anodized
- bcg
- M16 Profile, MPI Tested, Chrome Lined
- chargingHandle
- GRIP-N-RIP, 7075-T6 Aluminum, Ambidextrous
- muzzleDevice
- DD Flash Suppressor, 17-4 PH SS, Salt Bath Nitride
- threadPitch
- 1/2x28
- weight
- 3.5 lbs
- madeIn
- USA
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Build Your Custom Configuration
Add the Daniel Defense MK18 Upper Receiver Group to your build and see how it enhances your platform.