User Ratings
No ratings yet
Be the first to review this product
Complete AR-15 upper receiver assembly in .300 AAC Blackout with 8-inch barrel and M-LOK free-float handguard. Includes bolt carrier group and A2-style muzzle device. Features 1:8 twist, 5/8x24 barrel threading, black finish. Aligns with BU-300-8 variant for the same SKU.
Specifications
- Manufacturer:
- TacFire
- Category:
- upper-receiver
- Caliber:
- .300 AAC Blackout
- Platforms:
- AR-15
- Length:
- 8.0"
- UPC:
- 729205511387
- MPN:
- BU-300-8
- Required Component:
- Yes
Parts Cabinet
Track parts you own or plan to buy.
Where to Buy
Have one to sell?
Sponsored
MantisX
The smart way to train your AR build
Built your rifle — now train it. BlackBeardX installs in minutes and turns your AR into a full dry fire system with smart feedback on every pull.
Shop BlackBeardXPrice History
Current
$269.49
Lowest
$241.33
Highest
$354.01
Price Alert
Sign in to save a target price and receive an email when this component drops.
Sign In to Set AlertWhat's Included in this Bundle
Similar Products
Bravo Company BCM4 Upper Receiver Assembly Flat Top With Forward Assist 1913 Rail
Bravo Company Manufacturing (BCM)
$129.00
Aero Precision AR-15 Assembled Upper Receiver, Black (APAR501603AC)
Aero Precision
$111.99
BCM MK2 Flat Top Upper Receiver Assembly, Black (BCM4-UR-MK2)
Bravo Company Manufacturing (BCM)
$129.95
BCM M4 Upper Receiver Assembly, 7075-T6, Black Anodized (4URM4)
Bravo Company Manufacturing (BCM)
$137.04
LMT Monolithic Upper Receiver - AR-15 - MRP-L - M-LOK - Specwar - 11.5"
LMT
$940.50
BCM MK2 12.5" 5.56 Carbine Barreled Upper with MCMR-10 Handguard
Bravo Company Manufacturing (BCM)
$820.39
BCM MK2 BFH 11.5" 5.56 Carbine Barreled Upper with MCMR-10 Handguard
Bravo Company Manufacturing (BCM)
$903.99
Aero Precision AR-15 Assembled Upper Receiver, Kodiak Brown Anodized (APAR501664AC)
Aero Precision
$98.00
Builds Using This Part
No builds yet — be the first to use this part.
Related Guides
Guide
5.56 vs .223 vs .223 Wylde: Which Ammo Is Safe in Which Chamber
A 5.56 NATO or .223 Wylde chamber fires both cartridges; a .223 Rem chamber should not fire 5.56. Leade, pressure, barrel markings, and which chamber to pick.
5 min read
Guide
AR-10 Receiver Patterns: DPMS vs. Armalite Compatibility
The AR-10 has two incompatible receiver patterns — DPMS and Armalite — that look similar but do not share parts. This guide explains the differences and how to buy correctly.
6 min read
Guide
The AR-10 Platform: What It Is and How It Differs from the AR-15
A practical overview of the AR-10 — its origins, how it differs from the AR-15, available calibers, and when it makes more sense than a standard AR-15 build.
6 min read