Surplus Colt M4A1 SOCOM Block I Upper

FIRST PICTURE IS FOR DEMONSTRATION ONLY! NO AIMPOINT, LASER OR HANDGUARD INCLUDED

DIY Surplus Colt M4A1 SOPMOD builders kit. Comprised of all clone correct parts & a new barrel so there will be no issues putting rounds through this. This kit DOES NOT COME ASSEMBLED!

The SOPMOD M4A1 upper receiver is a modular enhancement of the standard M4A1 Carbine, designed to improve versatility, reliability, and effectiveness in a wide range of combat environments. It is part of the broader SOPMOD accessory kit issued to SOCOM units.

Core Features:

• Receiver Body:

  • Standard mil-spec forged Colt upper receiver.

  • Constructed from 7075-T6 aluminum, hardcoat anodized in black or dark gray.

  • Features M4 feed ramps for improved feeding reliability.

• Barrel:

  • Typically a 14.5-inch cold hammer-forged SOCOM profile barrel.

  • Chambered in 5.56x45mm NATO.

  • Chrome-lined or sometimes phosphate-coated for durability and corrosion resistance.

  • 1:7 twist rate for optimal stabilization of heavier bullets (like 62gr M855 or 77gr Mk 262).

• Rail Interface System (RIS) / Rail Adapter System (RAS):

  • Block I: Equipped with the Knight’s Armament Company (KAC) RAS, a drop-in quad rail system allowing attachment of various accessories.

  • Block II: Upgraded to the Daniel Defense RIS II, a free-floating quad rail for improved accuracy and rigidity.

  • Full-length Picatinny rails (MIL-STD-1913) on the top, sides, and bottom.

• Muzzle Device:

  • Standard A2 birdcage flash suppressor on early models.

  • Often replaced with SureFire SOCOM muzzle brakes or flash hiders for suppressor compatibility (e.g., SOCOM RC suppressors).

• Bolt Carrier Group (BCG):

  • Standard mil-spec BCG, often with enhanced coatings (phosphate, nickel-boron, or chrome) depending on the unit.

  • High-quality gas key staking for reliability.

• Gas System:

  • Carbine-length direct impingement gas system.

• Sights and Optics:

  • Backup iron sights: KAC/Matech flip-up rear sight and fixed or flip-up front sight.

  • Compatible with a range of optics including:

    • ACOGs (e.g., TA01NSN or TA31)

    • Aimpoint Comp M2/M4

    • EOTech EXPS or SU-231A/PEQ

    • Laser aiming modules like AN/PEQ-2, PEQ-15 ATPIAL

PARTS LIST:

-Surplus Colt C Stamp M4 Upper - Square Forge or Cerro (dependent on availability)

-NEW! Capco CAGE Code 14.5" SOCOM Heavy Profile Barrel

-Surplus Colt Charging Handle

-Surplus A2 Birdcage

-Surplus Colt Gas Tube

-Surplus Colt Delta Ring

This kit DOES NOT COME ASSEMBLED! You will have to assemble it yourself. Simple tools such as a reaction rod, hammer, punches & barrel nut wrench will be required.

FIRST PICTURE IS FOR DEMONSTRATION ONLY! NO AIMPOINT, LASER OR HANDGUARD INCLUDED