Ballistic Advantage Premium Fluted Stainless Barrels – 6mm ARC (12.5", 16", 18")

Product Overview

These are the same Ballistic Advantage Premium Fluted Stainless barrels we trusted in our original MUTT rifle development and testing—now available as standalone components through Ally Munitions.

Ballistic Advantage has earned a strong reputation for producing barrels that consistently meet or exceed their 1 MOA accuracy guarantee, and our in-house testing has confirmed that these barrels deliver excellent performance across a wide variety of factory and handloaded 6mm ARC ammunition.

We currently offer three fluted stainless configurations:

• 12.5" Compact DMR

• 16" Mid-Length General Purpose

• 18" SPR Rifle-Length Precision

Each barrel is built from 416R stainless steel, deeply fluted for improved cooling and weight reduction, and optimized for real hunting and field use.

Ally Munitions Inspection & Quality Control (Applies to Every Barrel)

Every single barrel offered on our site is fully inspected in-house before it is ever uploaded for sale.

Our inspection process includes:

• Complete visual QC

• Gas port verification and gauging

• Full bore scoping to ensure internal quality

• Chamber and crown inspection

• Receiver fitment checks

• Headspace verification (matched to the BCGs we offer)

Each barrel ships with a printed inspection report, and all inspection data is documented internally.

If a barrel does not meet our standards, it never makes it onto the website—period.

Barrel Options & Specifications

12.5" 6mm ARC Premium Fluted DMR Barrel

Compact Hunting & Suppressed Setup Favorite

The 12.5" DMR fluted barrel is an outstanding option for hunters building a compact ARC rifle. We’ve been extremely impressed with our own test samples, and this length is ideal for maneuverable setups while still delivering excellent ballistic performance.

Specifications

• Length: 12.5"

• Caliber: 6mm ARC

• Material: 416R Stainless Steel (Premium Series)

• Twist Rate: 1:7

• Profile: Premium Fluted DMR

• Gas System: Carbine Length

• Gas Journal Diameter: 0.750"

• Gas Port Size: 0.063"

• Muzzle Thread: 5/8x24

• Finish: Stainless Steel

• Chambered & Headspaced: By Ballistic Advantage (verified in-house)

Perfect for compact hunting rifles, suppressed predator rigs, and lightweight field builds.

16" 6mm ARC Premium Fluted Barrel + CMC Mid-Length Gas Tube

The Proven MUTT Standard

This is the exact barrel configuration used in our original MUTT builds. The 16" length offers one of the best balances of velocity, handling, and reliability in the ARC platform.

Specifications

• Length: 16"

• Caliber: 6mm ARC

• Material: 416R Stainless Steel (HP & MP tested)

• Twist Rate: 1:7

• Profile: Premium Fluted

• Gas System: Mid-Length

• Gas Journal Diameter: 0.750"

• Gas Port Size: 0.075"

• Muzzle Thread: 5/8x24

• Includes: CMC Mid-Length Gas Tube

• Finish: Stainless Steel

• Chambered and Headspaced: By Ballistic Advantage (verified in-house)

This is a true do-all ARC barrel with consistent sub-MOA capability.

18" 6mm ARC Premium Fluted SPR Barrel

Maximum Velocity & Long-Range Stability

The 18" SPR profile is optimized for shooters looking to stretch the ARC platform farther. Rifle-length gas provides a smooth recoil impulse and excellent stability for precision-oriented builds.

Specifications

• Length: 18"

• Caliber: 6mm ARC

• Material: 416R Stainless Steel (Premium Series)

• Twist Rate: 1:7

• Profile: Fluted SPR

• Gas System: Rifle-Length

• Gas Journal Diameter: 0.750"

• Gas Port Size: 0.098"

• Muzzle Thread: 5/8x24

• Feed Ramps: M4

• Finish: Stainless Steel

• Chambered & Headspaced: By Ballistic Advantage (verified in-house)

A natural choice for SPR-style uppers and longer-range ARC performance.

Included With Every Barrel

Every barrel ships with a properly matched gas tube wrapped inside the packaging.

We also recommend pairing these barrels with the inspected BCGs we offer, as proper headspace and gas alignment are key to long-term reliability.

Installation Notes

• These barrels feature a 0.750" gas journal

• Barrels are not factory-dimpled

• Adjustable gas blocks are strongly recommended for suppressed use

• We suggest applying a small amount of semi-permanent thread locker to gas block screws

• Proper torque and alignment matter more than dimpling alone

Performance Notes

• Deep fluting improves cooldown and reduces weight

• Excellent reliability across factory 6mm ARC loads

• Proven compatibility with CMC components

• Consistent headspacing and gas alignment when built correctly

Ally Munitions Build Recommendation

Before building, determine your intended use:

• Suppressed hunting rifle? Go heavier on buffer weight and use an adjustable gas block

• Flow-through suppressor? Standard tuning is often sufficient

• Unsuppressed? Flat wire springs and heavier buffers provide excellent recoil control

The 6mm ARC has significantly more case capacity than 5.56, and it benefits from proper buffer tuning.

Important Packaging Note

Open packaging carefully—gas tubes are wrapped inside with the barrel and can be missed if opened too quickly.

Disclaimer & Warranty Notice

Ballistic Advantage barrels carry a manufacturer 1 MOA accuracy guarantee. While every barrel we sell is fully inspected and quality-checked in-house, accuracy and function can be heavily influenced by factors outside of the barrel itself, including:

• Upper receiver fit

• Bolt and headspace variables

• Gas system setup and tuning

• Ammunition selection

• Assembly torque and alignment

• Suppressor backpressure

• Shooter fundamentals and optic setup

Our inspection process is designed to catch any barrel-related issues before sale, but final performance is dependent on the complete rifle build.

If you experience any issues with your barrel or build, please reach out to us directly. We want to make note of it, help troubleshoot where possible, and ensure you are taken care of.

Legal & Compliance Disclaimer (Barrel Length Notice)

Barrel length and firearm configuration are the responsibility of the purchaser.

Some barrel lengths—particularly those under 16 inches—may be subject to additional federal regulation under the National Firearms Act (NFA) when installed on certain firearm platforms.

It is the customer’s responsibility to ensure:

• Proper compliance with all applicable ATF regulations

• Correct firearm classification (rifle, pistol, SBR, etc.)

• Any required tax stamps, registration, or legal documentation prior to assembly

• Full adherence to all local, state, and federal laws regarding barrel length and firearm configuration

Ally Munitions does not provide legal advice. By purchasing this product, you acknowledge that you understand and will comply with all relevant firearms laws before installation or use.