Daniel Defense MK18 RIII URG | 5.56 NATO | 10.3″

The Daniel Defense MK18 RIII URG is an AR-style upper assembly built around a 10.3″ barrel chambered for .223 Rem/5.56 NATO. It pairs a compact barrel and URG-style rail to support short-barrel builds for users who need a compact, maneuverable upper. Common applications include close-quarters training and competition stages that demand quick handling and fast transitions.

Product Specifications

• The UPC is 818773023016.
• The manufacturer is listed as Daniel Defense.
• The model name is MK18 RIII URG as provided in the product title.
• The caliber is listed as .223 REM/5.56 NATO.
• The barrel length is 10.3″.
• The rate of twist is 1-in-7″.
• The muzzle thread pattern is 1/2×28.
• The handguard is listed as FDE RIS III 9.5″ M-LOK Rail in the attributes.
• The gas system is listed as Carbine Length Gas System.
• The charging handle is listed as GRIP-N-RIP Charging Handle.
• The product is described as having a Threaded Barrel (special attribute).
• The listed unit weight is 4.50 (as provided in source data).
• Sights are listed as No Sights.
• The country of origin is US.

This upper is built for compact AR-15 style configurations where a shorter barrel and responsive handling are priorities. Its combination of a 10.3″ barrel, URG-compatible rail geometry, and a 1/2×28 threaded muzzle make it suitable for builds intended for close-quarters training or dynamic competition stages; verify local and federal laws before assembling or registering regulated items.