Geissele Automatics Mk16 14.5'' Urgi Upper Chf Barrel Ach Rebcg 5.56Mm Ddc

The Geissele Automatics Mk16 14.5" URGI upper receiver is a complete, combat-proven upper built on the USASOC platform that's been trusted by professional shooters and military units for reliability under real-world conditions. If you're building or upgrading an AR-15 for hunting, tactical training, or long-range shooting, this upper brings together quality components engineered to work as a cohesive system: a hammer-forged, chrome-lined barrel, Geissele's Reliability Enhanced Bolt Carrier Group, and the modular MK16 handguard that lets you configure your rifle exactly how you need it.

What makes this upper stand out is the attention to detail in execution. The 14.5" barrel is Government profile with a mid-length gas system, designed for the 5.56mm cartridge with a 1/7 twist rate. It ships pinned and welded with a SureFire SF4P flash hider for a permanently configured muzzle that meets legal requirements where needed. The Super 42 buffer spring and H1 buffer give you a balanced, reliable operating cycle, while the low-profile gas block is pinned in place for bombproof durability.

The Geissele Airborne Charging Handle in DDC finish pairs with the MK16 handguard—a Super Modular Rail design available in 9.3", 10.5", or 13.5" lengths depending on your preferred setup and shooting style. This upper accepts standard AR lower receivers and plays nice with M855A1 ammunition and beyond. Whether you're a precision rifle enthusiast, competitive shooter, or someone who values mil-spec reliability without the marketing noise, the Mk16 URGI upper delivers performance that doesn't need hype to back it up.

Key Features

• 14.5" Government profile, chrome-lined, hammer-forged barrel with 1/7 twist for 5.56mm
• Mid-length gas system for balanced recoil and reliability
• Geissele Reliability Enhanced Bolt Carrier Group for consistent performance
• Geissele Airborne Charging Handle in DDC finish
• Geissele Super Modular Rail MK16 handguard (select length)
• SureFire SF4P 4-prong flash hider, pinned and welded
• Low-profile Super Gas Block, pinned in place
• Super 42 buffer spring and H1 buffer included
• Mil-spec M4 upper receiver assembly
• Designed for full-power cartridges including M855A1

Specifications

Frequently Asked Questions

Will this upper receiver work with my AR-15 lower?

Yes. The Mk16 URGI is a mil-spec M4 upper assembly that's compatible with any standard AR-15 lower receiver (your stripped or assembled lower, in any configuration you prefer).

Is the muzzle device pinned and welded?

Yes. The SureFire SF4P flash hider comes pinned and welded to the 14.5" barrel, so the muzzle is permanently configured and meets legal requirements for permanent attachment.

What handguard length comes with this upper?

The Geissele Super Modular Rail MK16 is available in three lengths: 9.3", 10.5", or 13.5". The specific length included is determined by your selection at checkout; please verify which length you're ordering.

What buffer weight is included with the 14.5" barrel?

An H1 buffer is included with this 14.5" configuration, paired with the Super 42 buffer spring for optimized cycling.