LBE Unlimited Ready Build Kit 5.56 NATO 13.7" CHF Complete Upper

The LBE Unlimited Ready Build Kit is a complete AR-15 upper receiver assembly built around a 13.7" cold hammer forged (CHF) barrel chambered in 5.56x45mm NATO (also handles .223 Remington). Purpose-built for AR pistol and SBR builds, this upper combines compact handling with the durability of a hammer-forged bore for reliable cycling across duty, defense, and range use.

The kit pairs a complete upper receiver with a mid-length gas system, a free-floating handguard, a full-mass M16 bolt carrier group, and a classic A2 flash hider. The 13.7" CHF profile is well suited for pinned-and-welded muzzle device setups that reach the 16" minimum overall length while preserving a short, quick-handling front end. Finished in black throughout, this upper drops onto any mil-spec AR-15 lower receiver.

• Complete upper receiver
• 13.7" cold hammer forged barrel
• Mid-length gas system
• Free-floating handguard
• M16 bolt carrier group
• A2 flash hider

Drop the Ready Build Kit onto any mil-spec AR-15 lower to complete the build - ideal for a compact AR pistol, an SBR project, or a general-purpose carbine upper.