AR-15 Parts & Build Kits

Everything you need to build, upgrade, or customize your AR-15. Stripped lowers, complete uppers, mil-spec triggers, handguards, buffer kits, and more.

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AR-15 Lower Receivers

Stripped and complete lower receivers from trusted manufacturers.

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Complete Upper Assemblies

Barreled uppers in 5.56 NATO, .223 Wylde, and .300 BLK.

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AR-15 Build Kits

Complete kits minus the stripped lower. Rifle, pistol, and SBR configurations.

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Triggers & FCGs

Drop-in triggers, mil-spec fire control groups, and match triggers.

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Bolt Carrier Groups

Nitride and phosphate BCGs. MPI tested. Full-auto rated carriers.

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Parts & Accessories

Buffer kits, charging handles, gas blocks, muzzle devices, and LPKs.

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Fast ShippingSame-day on orders before 2 PM
Secure CheckoutAll major cards accepted
30-Day ReturnsHassle-free on unused items
US-BasedShips from our US facility

Build Your AR-15 From the Ground Up

AR-15 Parts Direct carries a complete selection of AR-15 components for builders and shooters. Whether you are starting from a stripped AR-15 lower receiver and need a complete ar15 build kit, or looking for a drop-in AR-15 trigger upgrade, our inventory covers every step of the build.

We stock AR-15 upper receivers in popular barrel lengths — 16″ for rifles, 10.5″ and 11.5″ for pistol and SBR builds. All uppers are chambered in 5.56 NATO or .223 Remington with chrome-lined or nitride-treated bores. Our AR-15 accessories section includes mil-spec buffer tube kits, enhanced bolt carrier groups, ambidextrous charging handles, adjustable gas blocks, and free-float M-LOK handguards.

For shooters who want a turnkey solution, our AR-15 build kits include everything you need minus the stripped lower — upper assembly, lower parts kit, buffer kit, and stock. Just add your serialized AR-15 lower receiver and you have a complete rifle ready for the range.