AR-15 300 Blackout 10.5″ Pistol Build Kit (Unassembled) – Purple

Shooters Gate
SKU:
AR-BDKT-U300-10.5P8C-M10-PP
$485.99
(1 review)
Weight:
6.00 LBS
Current Stock:

Out of stock

Out of Stock
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300 Blackout 10.5
AR-15 300 Blackout 10.5" Pistol Upper Complete Build Kits
$251.19
Best price in cart
- OVERVIEW -
The Shooters Gate AR-15 Unassembled Build Kit provides a solid Mil-Spec foundation for a dependable 300 Blackout build. It includes a Stripped upper receiver, a 10.5" 300 Blackout barrel with a mid-length gas system (twist varies depending on the barrel), and a Purple 10" free-float M-LOK handguard for stability and accessory mounting.

The kit also features a Bolt Carrier Group, made in the USA, standard charging handle, complete lower parts kit, and a Pistol buffer tube assembly. Bonus tools—an armorer’s wrench, gun mat, and sling—are included to support assembly. Only a stripped lower receiver and magazine are required to complete the build.
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Upper Assembly

Upper Receiver
Stripped upper receiver
Barrel
10.5" 300 Blackout barrel
(twist varies depending on the barrel)
Dust Cover & Forward Assist
  • Purple dust cover
  • Purple forward assist
Gas System
  • Gas Block (diameter varies depending on the barrel)
  • Gas Tube (length varies depending on the barrel)
Muzzle Device
A2 Bird Cage Flash Hider with crush washer
Handguard
Purple M-LOK Free Float Handguard
For 10.5" Uppers there will be a 10" handguard
BCG & Charging Handle
  • Bolt Carrier Group, made in the USA
  • Black standard charging handle

Buffer System

Included Parts
Pistol Buffer Tube Buffer Spring Buffer Castle Nut End Plate

Lower Parts Kit

Included Parts
Safety Selector Safety Detent Safety Detent Spring Trigger Guard Trigger Guard Roll Pin Pistol Grip Washer Pistol Grip Screw Buffer Retainer Retaining Spring Mag Release Mag Release Button Mag Release Spring Takedown Pins (x2) Takedown Springs (x2) Takedown Detents (x2) Hammer Spring Hammer Pin Trigger Spring Trigger Pin Bolt Catch Bolt Catch Plunger Bolt Catch Spring Bolt Catch Roll Pin Disconnector Disconnector Spring Trigger Guard Screws Trigger Hammer AR-15 Pistol Grip

To Complete Your Build

What You Still Need
  • AR-15 Stripped Lower Receiver (FFL & Background Check required)
  • Magazine suitable for your desired caliber
⚠ WARNING: This product can expose you to chemicals such as lead and other petroleum products which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.p65warnings.ca.gov

Reviews

  • 5
    Good!!!

    Posted by Michael Chen on Jan 4th 2026

    Build quality is really good. Exactly what I expected.