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Complete Rifle Build Kit – 300 Blackout (16″ Barrel & 15″ Lightweight Keymod Handguard) AR 15

$650.00 $550.00 (You Save $100.00)

Complete Rifle Build Kit - 300 Blackout (16" Barrel & 15" Lightweight Keymod Handguard) AR 15
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Free Shipping on all orders $325+!

SKU: UA300CHB1618(P).750-(15)LWKM_Budget


Want an AR upper that’s super lightweight, while retaining the most rail space possible? Looking for the most accurate, well-built AR capable of shooting subsonic suppressed and supersonic with one gas system and barrel? If that sounds expensive, you’re wrong. You’ve found the perfect AR Build Kit: Our 300 AAC blackout rifle upper comes with 16″ barrel and 15″ lightweight keymod handguard. This upper provides the most rail length with the least weight possible, and its profile, capability, and reliability make this AR upper assembly a standard go-to rifle for any level of operator.

Made in The USA

Sure, a lot of rifle parts are built in the States, but our 300 blackout rifle upper assembly is head and shoulders above the rest. Each upper assembly features a barrel constructed from 4150 chrome moly steel, with M4 feed ramps, standard flat top M4 upper receiver, keymod and picatinny rail attachments, type III hard coat anodized finish, and the expectation of providing 1-MOA accuracy at 100 yards if you’re good enough.

300 Blackout Rifle Barrel Features:

  • 300 AAC blackout chamber
  • 16″ with parkerized finish
  • 4150 chrome moly steel
  • Heavy profile
  • 1:8 twist rate
  • 5/8 x 24 thread pitch
  • A2 birdcage flash suppressor

300 Blackout Receiver Features:

  • 15″ keymod handguard
  • Carbine-length gas system (0.125 Hole)
  • Low profile gas block (0.750)
  • M4 flat top upper
  • M4 feed ramps
  • Carbine gas tube
  • Charging handle
  • Chrome-lined BCG

300 Blackout Build Kit Extras:

  • Buffer Tube and spring
  • Enhanced stock
  • Lower parts kit
  • 7075 80% forged lower receiver

No FFL Required

This complete, plug-and-play 300 AAC blackout build kit is the most effective way to finish your first 300 blackout AR-15 without any guesswork. The entire barrel and gas system are head spaced and pre-installed, and everything ships to your door with no FFL required and no paperwork needed!

Need a California-Compliant Build Kit? Follow These 4 Steps!

1. Choose “CA-Compliant Lower Parts Kit” in the Lower Parts Kit dropdown.

2. Choose the “No Lower Receiver” option for the 80% Lower Receiver dropdown.

3. Select/Click “Add to Build”.

4. Head here to purchase a California-compliant 80% lower receiver

Please note: This AR-15 Build Kit requires that the builder completes the 80% lower receiver themselves, but that’s the fun part (and the only way to build your own AR-15 without the need of an FFL transfer or serialization).

No FFL required Made in the USA Lifetime Warranty

Complete Rifle Build Kit – 300 Blackout (16″ Barrel & 15″ Lightweight Keymod Handguard) AR 15

$600.00 $500.00 (You Save $100 )

$600.00 $500.00 (You Save $100 )
Save For Later
Save For Later

Free Shipping on all orders $325+!


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