Daniel Defense M4A1 Upper Receiver 223 Rem/556NATO 14.5" Barrel (16" OAL with Pinned Brake) Carbine Length Gas System 1:7 Twist M4 12.0 Rail Flat Dark Earth Finish Fits AR 23-004-13150

The Daniel Defense M4A1 Upper Receiver Group features the M4A1 Rail Interface System (RIS II)" which has been in use by US Special Operations Command (SOCOM) for the SOPMOD II Weapons System since 2005. This two-piece" free-floating rail system allows the mounting of devices like a M203 grenade launcher without influencing the barrels harmonics" eliminating problems like wandering point of impact that plagued other mounting designs. The two-piece design also allows for partial disassembly of the rail to aid in cleaning around barrel without completely removing the entire rail system. The weight of anything attached to the RISII rail system is fully supported by a sturdy bolt-up system" using 6 grade 8 bolts" leaving the barrel completely free floating for best possible accuracy and dependability. The M4A1 features a 14.5" Cold Hammer Forged M4 Profile barrel with a permanently attached Daniel Defense Improved Flash Suppressor to meet the NFA required 16" length. All Daniel Defense complete upper receiver groups come standard with an M16 profile bolt carrier group.

UPPER RECEIVER: Mil-Spec with Indexing Marks and M4 Feed Ramps. CNC Machined of 7075-T6 Aluminum
BARREL: Chrome Moly Vanadium Steel, Cold Hammer Forged, 1:7 Twist, 14.5 M4 Profile, Chrome Lined, Mil-Spec Phosphate Coated"
GAS SYSTEM: Mil-Spec F-Marked Front Sight Base, Carbine Length, Direct Impingement
MUZZLE DEVICE: Surefire SF3P Flash Hider / Suppressor Adapter, Black Ionbond DLC Coating, Pinned and Welded to Barrel
BOLT CARRIER GROUP: M16 Profile, Mil-Spec MP Tested, Chrome Lined, Properly Staked Gas Key
SIGHTS: A1.5 Fixed Rear Sight, 6061-T6 Aluminum, Type III Hard Coat Anodized
HANDGUARD: Daniel Defense M4A1 FSP Rail Interface System (RIS) II, CNC Machined of 6061-T6 Aluminum, Type III Hard Coat Anodized FDE

Stock Notice: This item is NOT marked "In Stock". We will contact you within 12-24 hours by email if your order is on backorder with our distributor and will take longer than the 5-7 business days it takes us to ship out. Please do not order if you need this item shipped immediately.