Diamondback Firearms .300 Blackout AR-15 Barrel Nitride - 8.5"
Click to see full view
Diamondback
Overview
The Diamondback Firearms .300 Blackout AR-15 Barrel is an 8.5" heavy profile barrel designed specifically for the .300 Blackout caliber, making it an excellent choice for compact builds that prioritize maneuverability without sacrificing performance. With a pistol-length gas system and a 1:8 twist rate, this barrel is optimized for stability and accuracy, effectively stabilizing a range of bullet weights while providing reliable cycling in short-barreled applications. This barrel commonly appears in builds focused on tactical or close-quarters configurations where a short, powerful platform is desired.
Specifications
Build history on GunPartPicker
Builders have been adding the Diamondback Firearms .300 Blackout AR-15 Barrel Nitride - 8.5" to their builds on GunPartPicker since February 2026. All time, it ranks #222 of the 763 barrels builders have added.
Availability is good: it was in stock at one retailer or another nearly every day in August 2026, but today only Palmetto State Armory has it in stock. The best price crept up from $72.99 to $79.35 over August 2026. Buying today, the lowest price is $72.99 at Palmetto State Armory, which matches the best price we saw in August.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 31 retailers
Not sure which barrel to pick?
We ranked every barrel by how often it shows up in real builds on GunPartPicker.
Read the guide: AR-15 Barrel Length & Brand Report →Check it against the live catalog:
Frequently Built With
The part most often added in each category by the 9 builds that include this one
Aero Precision M4E1 Stripped AR-15 Lower Receiver - FDE Cerakote
Aero Precision AR-15 Stripped Upper Receiver, No Forward Assist Black
Rise Armament Super Sporting AR15/10 Single Stage Trigger - Flat - Dtom Special Edition
Tacfire's 7" ACE M-LOK Handguard for AR-15 - Black, Balance and Versatility in One - HG20-7
Strike Industries Arch AR-15 Charging Handle Standard Latch - Black
Bravo Company Manufacturing AR-15 Bolt Carrier Group - M16
Build Configuration Breakdown
Aggregated and anonymized data showing how builders use this product
PlatformBased on real build data showing which platform (AR-15, AR-10, AR-9) builders pair with this product.
No reviews yet. Be the first to review this product!