FN M4A1 Block 1 SOCOM Upper Receiver - 5.56 NATO

Limited production - Charlie's Exclusive

The FN M4A1 Block 1 SOCOM Upper Receiver is built for those who value authenticity and performance in their AR-15 builds. Featuring FN's legendary SOCOM barrel and precision components, this upper faithfully reproduces the military-issued configuration while meeting civilian requirements. Designed with attention to detail, it balances historical accuracy with modern functionality.

Features and Benefits

• FN 14.5” SOCOM Barrel: Chrome-lined and button-broached with a 1:7 twist for durability and optimized performance with heavier 5.56 NATO rounds.
• CAGE Code on Barrel: Military authenticity with FN’s CAGE code engraved directly on the barrel for collector value.
• Knight’s Armament RAS Rail: Trusted by operators, offering modularity for accessories while maintaining ergonomic handling with included rail covers.
• Magpul Folding Rear BUIS: Compact and reliable backup sight for enhanced versatility.
• Mil-Spec Bolt Carrier Group: FN’s precision MPI/HP-tested BCG ensures reliability under demanding conditions.

This is a custom build, made exclusively for Charlie's Custom Clones.  It is a limited production model, so we get very few in.  FN parts are very hard to source.  Our armament partners at Potomac Armory helped us with this.  Potomac Armory is known for building out some of the most authentic military correct uppers and rifles, and we are lucky to represent them.

Authenticity and Practicality

This upper receiver delivers on the expectations of collectors and tactical users alike by adhering closely to SOCOM specifications. The 14.5” barrel, with its SOCOM profile, is optimized for balance and performance in varied scenarios, from close-quarters environments to mid-range engagements. FN's precision machining and chrome-lining provide exceptional durability, making it a preferred choice for high-stress use.

The Knight’s Armament RAS rail adds modularity without sacrificing ergonomics, making it an ideal platform for mounting optics, lights, and other essential accessories. With FN’s renowned manufacturing quality, this upper combines historical accuracy with uncompromising reliability.

Specifications