AT3 Barrel Builder Kit – 10.5″ .300 Blackout Medium Profile Pistol Length Barrel, Gas Block, Gas Tube & BCG
or 4 interest-free payments of $52.25 with 
6 Magazines Per Order: Due to extreme volume, we are limiting sales of magazines to 6 per customer order. This applies to individual and bundled magazines. AT3 reserves the right to cancel any order over the 6 magazine limit.
- Free standard shipping on orders $139+ details
- 90-day no-hassle returns policy
- Backed by the AT3 Lifetime Warranty! what it covers
Product description
AT3 Barrel Builder Kit – 10.5 Inch .300 Blackout Barrel, Gas Block, Gas Tube, and BCG
Features
- Includes the barrel, gas system, and bolt carrier group for a 10.5 inch .300 Blackout AR-15 upper build
- Built around an AT3 10.5 inch .300 Blackout medium profile barrel with a pistol-length gas system
- Includes a low-profile .750 steel gas block, pistol-length stainless gas tube, and two gas tube roll pins
- Includes a complete AT3 black nitride bolt carrier group for 5.56 NATO and .300 Blackout
- Useful for .300 Blackout pistol, SBR, or suppressor-host upper builds
The AT3 Barrel Builder Kit gives you the core parts for building out the barrel, gas system, and BCG side of a compact .300 Blackout AR-15 upper. This kit pairs a 10.5 inch medium profile barrel with a pistol-length gas system, low-profile gas block, two gas tube roll pins, and a complete black nitride BCG.
Note: This kit is not assembled. Upper receiver, handguard, charging handle, muzzle device, and small installation tools are not included.
Specifications
- Brand: AT3 Tactical
- Model: Barrel Builder Kit – 10.5 Inch .300 Blackout Pistol-Length with BCG
- MPN: AT3-BBKIT-105-300BLK-MED-PIS-GB-GT-BCG
- Platform: AR-15
- Caliber: .300 Blackout
- Barrel Length: 10.5 inches
- Barrel Profile: Medium
- Gas System Length: Pistol
- Gas Block Journal: .750 inch
- BCG Finish: Black Nitride
What’s Included
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Warranty & returns
Backed by the AT3 Lifetime Warranty!
All AT3 Tactical Brand Products carry a lifetime warranty against manufacturer’s defects.
This includes AT3 Red Dot Sights, Handguards, Iron Sights, and any other product that carries the “AT3 Tactical” or “AT3™” name. For other brands (ex. Magpul or Troy), please refer to the manufacturer’s warranty policy.
In the event that your AT3™ product becomes unusable, we will repair or replace the product at no charge to you.
If we cannot repair your product, we will replace it with a product in perfect working order of equal or better physical condition. The warranty is fully transferable, but we may require information about the original purchase to validate the authenticity of the product.
If your product is in need of warranty service, please contact AT3 Tactical to start the process
Our contact info is available here. To expedite processing, please provide your order information and description of the defect.
Please note: The AT3 Lifetime Warranty does not cover loss, theft, intentional damage or cosmetic damage that doesn’t affect the performance of the product.
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.
