AT3 10.5" .300 Blackout AR-15 JNL Ready Build Kit

$602.11

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SKU: AT3-JNL-RBK-105-300BLK-12SPEAR

Product description

AT3 10.5 Inch .300 Blackout JNL Ready Build Kit – 12 Inch SPEAR Pistol Upper

Uppers Built to Order – Ships Within 3 Business Days

Features

  • Just Needs Lower kit includes an assembled .300 Blackout pistol upper plus the parts needed to complete a stripped AR-15 lower receiver
  • 10.5 inch Ballistic Advantage .300 Blackout barrel uses a pistol-length gas system and 1:7 twist rate
  • 12 inch AT3 SPEAR handguard and KAK slimline flash can create a tucked muzzle-device layout
  • Assembled upper includes nickel boron BCG and standard mil-spec charging handle
  • Lower build components include mil-spec controls, fire control springs and pins, A2 grip, Magpul BSL brace, trigger guard, and carbine buffer assembly

The AT3 10.5 inch .300 Blackout JNL Ready Build Kit is built for customers who want the pistol upper already assembled and only need to supply a stripped AR-15 lower receiver. The kit combines a 10.5 inch .300 Blackout assembled upper with a 12 inch SPEAR handguard, KAK slimline flash can, nickel boron BCG, and charging handle, plus the lower components needed for a brace-equipped AR pistol lower.

Note: This kit includes an assembled pistol upper receiver and lower build components. Stripped lower receiver is not included, and lower parts are not assembled. This kit includes a pistol brace, not a rifle stock.

Warranty Note: Curated by AT3 Tactical. Components in this kit are covered by each manufacturer’s own warranty — AT3’s warranty does not extend to or replace the warranties of the individual parts included. Warranty terms for some component brands may not yet be listed in the warranty tab; contact the manufacturer directly for in-depth and up to date coverage details.

Specifications

  • Brand: AT3 Tactical
  • Model: 10.5 inch .300 Blackout JNL Ready Build Kit with 12 inch SPEAR Handguard
  • MPN: AT3-JNL-RBK-105-300BLK-12SPEAR
  • Platform: AR-15
  • Build Type: Just Needs Lower / assembled pistol upper with lower build components
  • Upper Receiver: AT3 10.5 inch .300 Blackout Complete Assembled Pistol Upper with Nickel Boron BCG and Mil-Spec Charging Handle
  • Caliber: .300 Blackout
  • Barrel Length: 10.5 inches
  • Barrel: Ballistic Advantage Modern Series 4150 CMV nitride barrel
  • Twist Rate: 1:7
  • Gas System: Pistol-length
  • Muzzle Thread: 5/8×24
  • Muzzle Device: KAK Slimline Flash Can
  • Handguard: 12 inch AT3 SPEAR M-LOK handguard
  • Bolt Carrier Group: AT3 5.56 NATO/.300 Blackout Nickel Boron M16 BCG
  • Charging Handle: AT3 Standard GI Charging Handle
  • Brace: Magpul BSL AR-15 Pistol Arm Brace
  • Grip: AT3 AR-15 A2 Mil-Spec Pistol Grip
  • Trigger Guard: STNGR Mil-Spec 7075 Trigger Guard Assembly
  • Buffer System: Carbine buffer assembly
  • Buffer Weight: 3.0 oz
  • Color: Black

What’s Included

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Warranty & returns

90-day no-hassle returns

The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.

If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.

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