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Ar-15 Modern Series Barrels .300 Blackout - Ar-15 Pistol Length 6 Barrel .300 Blackout
Our editorial team reviews specifications, product data, and field-use information to keep pages accurate.
$147.99
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SKU: 915000046
Overview
Built for compact .300 Blackout pistol setups, this 6-inch Modern Series barrel is intended for shooters configuring a short firearm around the cartridge. It is machined from 4150 Chrome Moly Vanadium steel and finished with a QPQ corrosion-resistant treatment, with a QPQ coated M4 feed ramp extension. The .750" gas block journal and 1:7 twist rate provide the listed configuration details for matching compatible components. All NFA/ATF rules apply, so it is important to verify lawful use before purchase or installation.
Why Hunters Choose the Ballistic Advantage
6-inch Modern
Series barrel chambered in .300
Machined From
4150 Chrome Moly Vanadium steel
Qpq Corrosion
Resistant finish
Qpq Coated
M4 feed ramp extension
.750-inch Gas
Block journal
Key Features
- 6-inch Modern Series barrel chambered in .300 Blackout
- Machined from 4150 Chrome Moly Vanadium steel
- QPQ corrosion resistant finish
- QPQ coated M4 feed ramp extension
- .750-inch gas block journal
- 1:7-inch twist rate
Best Used For
- Hunters building a .300 Blackout pistol configuration within NFA/ATF rules.
- Shooters needing a 6-inch Modern Series barrel for compact AR-15 setups.
- Users wanting a barrel with a .750-inch gas block journal and 1:7 twist.
- Builders specifying 4150 Chrome Moly Vanadium construction with QPQ finish.
- Owners of registered SBR, machine gun, or pistol lowers using this barrel legally.
Specifications
| Barrel Length | 6 inch |
|---|---|
| Blade Finish | QPQ Corrosion Resistant |
| Caliber | 300 Blackout |
| Compatible Lower Receiver Types | Registered SBR, Machine Gun, or Pistol |
| Feed Ramp Extension | QPQ coated M4 feed ramp extension |
| Gas Block Journal | .750" |
| Material | 4150 Chrome Moly Vanadium |
| Nfaatf Notice | All NFA/ATF Rules Apply |
| Possession Restriction | Possession of this barrel along with a Non-NFA lower receiver is Prohibited, except when installed on a Pistol configuration firearm |
| Twist Rate | 1:7 inches |
Pros
- 6-inch Modern Series barrel chambered in .300 Blackout
- Machined from 4150 Chrome Moly Vanadium steel
- QPQ corrosion resistant finish
- QPQ coated M4 feed ramp extension
- .750-inch gas block journal
- 1:7-inch twist rate
Considerations & Trade-offs
- The 6-inch length is a specialized pistol-length option, so it is not a general-purpose barrel choice for every .300 Blackout setup.
- This barrel is tied to specific NFA/ATF compliance requirements; possession and use depend on the receiver configuration and legal status of the firearm.
- The .750" gas block journal and 1:7 twist rate are fixed specifications, so compatibility should be checked against the intended build before purchase.
- The QPQ finish and coated feed ramp extension are part of the design, but they do not remove the need to match the barrel to the rest of the rifle or pistol system.
Suggested Comparisons
- AR-15 pistol barrels
- AR-15 .300 Blackout barrels
- Short-barreled rifle and pistol-length barrel components
- AR-15 barrel accessories and gas system parts
Suggested Accessories
- Gas block
- Barrel nut
- Upper receiver
- Muzzle device
Frequently Asked Questions
What cartridge is this barrel chambered for?
It is chambered in .300 Blackout.
What is the barrel length?
The product is a 6 inch barrel.
What material and finish are listed for this barrel?
The listed material is 4150 Chrome Moly Vanadium steel, and the finish is QPQ Corrosion Resistant Finish.
What are the listed gas block journal and twist rate?
The gas block journal is .750 inch, and the twist rate is 1:7 inches.
Are there any legal restrictions mentioned for this barrel?
Yes. The description states that all NFA/ATF rules apply, and that possession with a non-NFA lower receiver is prohibited except when installed on a pistol configuration firearm.