The LBE Unlimited Ready Build Kit (brand part number AR145RBK) centers on a 14.5-inch Cold Hammer Forged barrel chambered in .223 Remington/5.56 NATO, built by LBE UNLIMITED for a pistol-length gas system. This kit ships as a complete upper receiver with a free-floating handguard, gas block, and gas tube already installed, giving builders a close-quarters AR platform with the extra durability that comes from cold hammer forging. It is designed and marketed for AR pistol or registered SBR builds rather than a standard 16-inch-plus rifle configuration.

Key Specifications

• Barrel length is 14.5 inches, cold hammer forged for durability.
• Chambered in .223 Remington/5.56 NATO.
• Runs a pistol-length gas system for a compact build.
• Ships as a complete upper receiver ready to mate with a lower.
• Handguard is free-floating for improved accuracy potential.
• Includes a matched gas block and gas tube installed as part of the assembly.
• Marketed for AR pistol or short-barreled rifle builds given the sub-16-inch barrel.
• Precision-machined construction is engineered for durability and high performance.
• Sold as a complete Kit rather than a bare barrel alone.

Frequently Asked Questions

Why is this listed for pistol or SBR builds? At 14.5 inches, the barrel is under the 16-inch federal rifle minimum, so it is intended for an AR pistol lower or a properly registered Short-Barreled Rifle.

Do I need to register anything to buy this kit? No, purchasing the bare upper does not require any NFA paperwork; registration only becomes relevant if you later pair it with a shouldered rifle-configured lower.

Buy the LBE Unlimited 14.5-inch Ready Build Kit

Get a close-quarters-ready AR-15 upper built around a durable hammer-forged barrel. Order this AR-15 upper from our Lubbock, Texas gun shop for fast, insured shipping to your door.