The “AIR-GAUGED” Premium Barrel 3012CM7AIR is a Douglas 30 Caliber 1-12 Twist #7 Chrome Moly Barrel, purpose-built for shooters and gunsmiths who want true match-grade accuracy from a classic .30-caliber platform. This XX-grade, air-gauged barrel blank is crafted from 4140 chrome moly steel in a #7 medium-heavy contour, delivering the consistency, rigidity, and uniformity needed for serious long-range hunting and precision target work. prod.brownells.com+2Brownells UK+2
If you’re planning a .308-class custom rifle build or rebarrel—whether in .308 Winchester, .30-06, or other compatible .30-cal cartridges—the Douglas 3012CM7AIR “Air-Gauged” Premium Barrel offers the quality foundation you need for tight groups and reliable performance.
Douglas “Air-Gauged” XX Premium – Top of the Line
Douglas’s Air-Gauged Premium barrels sit at the very top of their product line:
This rigorous QC process is why Douglas Air-Gauged barrels are a frequent choice in high-end custom builds and precision rebarrel projects.
30 Caliber (.308) with 1:12 Twist – A Classic, Versatile Setup
The 3012CM7AIR is configured for 30 caliber (.308") bullets with a 1:12" twist rate: prod.brownells.com+2Brownells UK+2
A 1:12 twist is a time-tested choice that works especially well with many medium-weight .30-cal bullets, typically in the 150–168 grain range, and can perform well with other weights depending on bullet design and load. Ammunitions for Sale
That makes it an excellent option for:
Big-game hunting rifles in .308 Win or .30-06 where classic bullet weights dominate.
General-purpose precision rifles where you want stability and good long-range performance without over-spinning lighter bullets.
If you like the versatility and availability of .30-cal projectiles, this twist rate gives you a broad selection of quality hunting and target bullets to work with.
#7 Medium-Heavy Contour – Stability Without Going Full Bull
Contour is critical for both handling and accuracy, and the #7 contour hits a practical sweet spot:
Contour: #7 – a medium-heavy rifle barrel profile chosen for rigidity and better heat control than light sporter profiles. prod.brownells.com+2Primary Tactical+2
Douglas Air-Gauged barrels in #7 contour are typically 27½" (69cm) long as finished blanks, providing a generous sight radius and excellent velocity potential. Primary Tactical+2Brownells UK+2
The muzzle end is marked for the tightest taper, helping your gunsmith index and finish the barrel for optimal accuracy. Primary Tactical+1
For long-range hunting, prone shooting, or bench work, this contour gives you stability and accuracy without the impractical weight of a true bull barrel.
4140 Chrome Moly Steel – Strong, Durable, and Finish-Friendly
The 3012CM7AIR is made from chrome moly steel, a proven barrel material:
Material: 4140 chrome moly steel – tough, durable, and well-suited for high-performance rifle barrels. prod.brownells.com+2Primary Tactical+2
Compatible with traditional finishes such as bluing or Parkerizing, and can also be coated with Cerakote or similar modern finishes after final machining.
Designed to deliver a long service life when paired with proper chambering, crown work, and maintenance.
If you prefer the feel and look of classic chrome moly barrels—and want something that can be finished to match your build—this blank is an excellent choice.
Air-Gauged Premium Barrel Blank – Ready for Custom Work
The “AIR-GAUGED” Premium Barrel 3012CM7AIR is supplied as a barrel blank, giving your gunsmith maximum control over the final configuration:
Style: Air-Gauged XX Premium blank. prod.brownells.com+2Brownells UK+2
Supplied unchambered, unthreaded, and uncrowned – your gunsmith cuts the shank, chamber, muzzle threads (if desired), and crown to your exact specs. Primary Tactical+2Brownells UK+2
#7 contour and 30-caliber bore allow chambering in a wide range of compatible .30-cal cartridges, as long as they’re appropriate for the rifle action and pressure levels.
That blank format is ideal for serious custom builds, letting you tailor:
Final length (shorter or full-length depending on your needs)
Chamber design (standard SAAMI or custom throats/freebore)
Muzzle treatment (standard crown, brake, suppressor threads, etc.)
Built for Match-Grade Accuracy
The 3012CM7AIR incorporates design and QC features that directly support tight groups and consistent hits:
Air-gauged bore ensures uniform diameter and minimal variation along the length of the barrel. Primary Tactical+2Brownells UK+2
Instrument-inspected straightness helps maintain a consistent point of impact and reliable harmonics. Brownells Deutschland+1
XX Premium-grade barrels from Douglas are hand-selected for uniformity to within approximately .0001", giving you an exceptional starting point for a true precision rifle. Brownells UK+1
When properly chambered and installed by a competent gunsmith—and paired with quality ammunition—this blank is capable of sub-MOA and often better performance.
Ideal Applications for the 3012CM7AIR Barrel
With its 30-caliber, 1:12 twist, #7 contour chrome moly configuration, the Douglas “AIR-GAUGED” 3012CM7AIR is particularly well-suited for:
Long-range hunting rifles in .308, .30-06, and other .30-cal cartridges using classic hunting bullet weights.
Precision target rifles, including F-Class style rifles and tactical/precision practice rigs in .308 Win.
Big-game rifles where accuracy, durability, and traditional .30-cal performance are desired.
High-end rebarrel projects on proven actions like the Remington 700, Savage 110, Winchester 70, and similar platforms (with appropriate gunsmithing). Ammunitions for Sale+1
If your goal is to build a rifle that combines classic .30-cal ballistics with modern match-grade barrel quality, this blank checks all the boxes.
Key Specifications – “AIR-GAUGED” Premium Barrel 3012CM7AIR
From Douglas and major retailers: GunBroker+4prod.brownells.com+4Brownells UK+4
Manufacturer: Douglas
Model / MFR Part #: 3012CM7AIR
Product Name: “AIR-GAUGED” Premium Barrel – 30 Caliber 1-12 Twist #7 Chrome Moly
Caliber: 30 Caliber (.308")
Twist Rate: 1:12"
Material: 4140 Chrome Moly Steel
Contour: #7 (medium-heavy)
Style: Air-Gauged XX Premium barrel blank
Length (typical blank): ~27½" (#7 contour, with some lines offering 30" X-long blanks in the series)
Configuration: Unchambered, unthreaded, uncrowned barrel blank
Category: Rifle barrel blank for custom builds and rebarrel projects
(Exact finished length, muzzle diameter, and weight will depend on how your gunsmith cuts and profiles the barrel.)
Why Choose the Douglas 3012CM7AIR “Air-Gauged” Premium Barrel?
You should choose this barrel blank if you:
Want a top-tier .30-caliber barrel with Douglas Air-Gauged XX Premium quality.
Prefer a 1:12 twist optimized for classic .30-cal hunting and target bullet weights.
Need a #7 contour chrome moly blank that balances stiffness, heat handling, and manageable field weight.
Are working with a skilled gunsmith and want a barrel that can realistically deliver match-grade accuracy once properly installed.
Value tight tolerances, rigorous QC, and proven performance from a long-established barrel maker.
For gunsmiths, precision shooters, and serious hunters looking to get the most out of a .30-cal build, the “AIR-GAUGED” Premium Barrel 3012CM7AIR – Douglas 30 Caliber 1-12 Twist #7 Chrome Moly is an outstanding, high-precision starting point for your next custom rifle.
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