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WP360 AR15 Assembled Upper Receiver Package – .223 / 5.56

The .223 / 5.56 package delivers reliable, precision performance built from premium American-made components. Featuring a forged 7075-T6 aluminum receiver machined to Mil-Spec standards and a 16" stress-relieved 4150 CMV barrel with corrosion-resistant QPQ Blacknitride finish, this upper is optimized for durability and accuracy. The .223/5.56 chamber balances the ability to safely fire both .223 Remington and 5.56 NATO ammo, making it a versatile choice for everything from competitive shooting to tactical applications. Equipped with a free-float 15" handguard, premium bolt carrier group, and metal flip-up iron sights, this fully assembled package is sighted in and ready to deliver dependable, accurate shots straight out of the box—all proudly made in the USA.

Upper Receiver

• Forged from 7075‑T6 aluminum

• Precision machined to mil‑spec M16/M4 specifications

• M4 feed ramps for reliable feeding

• Type III hard-coat anodized finish

• Laser‑engraved T‑marks (light)

• Forward assist and dust cover installed

• .250 takedown pin holes for universal fit

• 100% Made in the USA

Barrel

• 16" 5.56 NATO, Government profile

• 4150 CMV steel, stress relieved after rifling

• QPQ Blacknitride+™ corrosion‑resistant finish by H&M

• Mid‑length gas system with .750” journal

• Twist: 1:7 RH, optimized for heavier 5.56 rounds

• Air‑gauge tested with individually verified headspacing

• M4 barrel extension with QPQ feed ramp coating

• 11° target crown for superior accuracy

• Dimpled for easy gas block installation

• Weight: 29 oz

• 1/2‑28 muzzle threads

• 100% American Made

Handguard

• Free‑float design, machined from 6061‑T6 aluminum

• Length: 15" with continuous top Picatinny rail

• M‑LOK® slots at 3, 6, and 9 o’clock positions

• Anti‑rotation tabs for secure lockup (fits forged uppers; may require hand‑fit on billet)

• 6061‑T6 barrel nut, no indexing required

• Hard-coated anodized finish

• Inside diameter: 1.350"

• Weight with mounting hardware: 12.6 oz

• Compatible with low‑profile gas blocks

• 100% Made in the USA

Bolt Carrier Group (BCG)

• M16 style carrier – 8620 steel, H&M Black Nitride finish

• Bolt – 9310 steel, heat treated, shot peened, MPI/HPT tested (batch)

• Gas key – 4140 billet steel, properly seated with Grade 8 fasteners and staked for reliability

• Cam pin – 4140 steel, nitride treated for wear resistance

• Extractor – billet 4140 steel, heat treated, shot peened, phosphate coated with insert and Viton O‑ring

• Firing pin – 17‑4 H900 stainless steel, precision machined

• Final ground before plating for true fit

• Test-fired and inspected for proper function

• 100% Made in the USA

Charging Handle

• Standard AR15 mil‑spec design

• Machined from billet 6061‑T6 aluminum

• Black anodized finish

• Lightweight – 1.5 oz

• Proudly Made in the USA

Gas System

• Low profile .750 gas block – 4140 heat-treated steel, QPQ finish, set‑screw secured

• Stainless steel gas tube (mid‑length) with coiled roll pin

• 100% Made in the USA

Muzzle Device

• A2‑style Birdcage flash hider/compensator

• 4150 steel construction, black phosphate finish

• 1/2‑28 threading, includes crush washer

• 6 slot pattern with solid bottom to reduce dust signature

• Weight: 2.56 oz

Flip-up Iron Sights

• Built from high-quality aluminum alloy for rugged, reliable performance in any environment

• Spring-loaded pop-up action deploys instantly at the push of a button for fast target acquisition

• Compatible with all rifles using Picatinny or Weaver rail systems (Winchester, Remington, Colt, and more)

• Front sight adjustable for elevation; rear sight adjustable for smooth windage control

• Low-profile, flat-folding design stays out of the way when not in use

• Lightweight and compact to minimize bulk without sacrificing performance

• Includes front sight adjustment tool for quick and easy zeroing