20″ 6.5 Creedmoor AR10 / LR-308 4150 CMV Black Nitride Barrel
Strike the ideal balance between precision, velocity, and maneuverability with this 20-inch 6.5 Creedmoor AR10 / LR-308 barrel. Precision machined from 4150 Chrome Moly Vanadium (CMV) steel and finished with a durable black nitride treatment, this barrel is built to deliver exceptional accuracy while standing up to years of hard use.
Featuring a 1:8 twist, rifle-length gas system, .750″ gas block journal, 5/8×24 muzzle threads, and a factory-machined gas block alignment dimple, this barrel makes assembling a reliable precision rifle easier than ever. Whether you’re building a hunting rifle, designated marksman rifle, or long-range AR10, this barrel provides the performance serious shooters expect. Mid State Firearms also offers complete upper assemblies if you wish to have one that is properly assembled, test fired, and ready to go on your lower.
Specifications
- Caliber: 6.5 Creedmoor
- Barrel Length: 20″
- Material: 4150 Chrome Moly Vanadium Steel
- Finish: Black Nitride (QPQ/Melonite)
- Twist Rate: 1:8
- Gas System: Rifle Length
- Gas Block Journal: .750″
- Muzzle Threads: 5/8×24
- Gas Block Dimple: Yes, 180° opposite the gas port
- Platform: DPMS LR-308 / LR308 Pattern / Most DPMS-Compatible AR10 Receivers
Why Choose a 20-Inch 6.5 Creedmoor?
For many shooters, a 20-inch barrel represents the sweet spot for the 6.5 Creedmoor. It retains much of the cartridge’s excellent long-range performance while offering a lighter, more compact rifle than a traditional 24-inch precision setup.
The result is a rifle that’s equally comfortable on the range, in the field, or carrying through the woods during hunting season.
A 20-inch barrel offers:
- Excellent long-range capability
- Reduced overall weight
- Improved handling
- Faster transitions between targets
- Outstanding balance for hunting and precision shooting
- Plenty of velocity for modern match and hunting ammunition
Built from 4150 CMV Steel
4150 Chrome Moly Vanadium has long been one of the most trusted barrel steels for demanding applications. Combined with a modern black nitride finish, it delivers exceptional durability, corrosion resistance, and a smooth, hardened bore surface.
Benefits include:
- Outstanding barrel life
- Excellent heat resistance
- Increased surface hardness
- Superior corrosion protection
- Easy cleaning and maintenance
- Matte black finish that complements modern rifle builds
Whether you’re spending weekends at the range or putting miles on your rifle during hunting season, a nitride-treated CMV barrel is built for the long haul.
Precision Gas Block Alignment
This barrel includes a precision-machined gas block alignment dimple located 180 degrees opposite the gas port.
This feature helps simplify installation by providing an easy reference point for compatible set-screw gas blocks, helping ensure proper gas port alignment while reducing the chance of the gas block shifting under recoil.
Benefits include:
- Easier installation
- More consistent gas port alignment
- Secure gas block positioning
- Less guesswork during assembly
- Ideal for both experienced builders and first-time AR assemblers
Why 6.5 Creedmoor?
The 6.5 Creedmoor was designed from the ground up for accuracy at extended distances. Its efficient, high-ballistic-coefficient bullets retain velocity exceptionally well, resist wind drift, and produce manageable recoil, making it a favorite among precision shooters and hunters alike.
Popular uses include:
- Precision rifle competitions
- Long-range target shooting
- Steel matches
- Deer hunting
- Hog hunting
- Predator hunting
- Recreational long-range shooting
- Designated marksman rifle (DMR) builds
Its combination of flat trajectory, retained energy, and shootability has made the 6.5 Creedmoor one of today’s most respected precision rifle cartridges.
AR10 / LR-308 Compatibility
This barrel is designed for the DPMS LR-308 pattern, making it compatible with most large-frame AR receivers built to that specification.
Compatible with:
- DPMS LR-308 upper receivers
- DPMS-pattern AR10 rifles
- Standard rifle-length gas tubes
- .750 low-profile gas blocks
- 5/8×24 muzzle devices and suppressors
- DPMS-pattern .308 Winchester / 6.5 Creedmoor bolt carrier groups
Because 6.5 Creedmoor and .308 Winchester share the same case head dimensions, this barrel works with standard DPMS-pattern .308/6.5 Creedmoor bolts and bolt carrier groups. Simply pair it with the correct barrel and magazine to complete your build.
Why Buy From Mid State Firearms?
Mid State Firearms has specialized in AR-platform rifles and components for over 12 years. Our team understands what builders expect from a quality barrel, from proper machining and dependable compatibility to long-term durability.
When you shop with Mid State Firearms, you get:
- Experienced AR specialists
- Carefully selected quality components
- Fast shipping
- Excellent customer support
- Limited Lifetime Warranty on eligible Mid State Firearms manufactured products
Whether you’re assembling your first precision AR10 or upgrading an existing rifle, we’re committed to helping you build with confidence.
Complete Your Build
Finish your 6.5 Creedmoor build with compatible components from Mid State Firearms:
- DPMS LR-308 stripped and assembled upper receivers
- Free-float AR10 M-LOK handguards
- .308 / 6.5 Creedmoor bolt carrier groups
- Ambidextrous charging handles
- Low-profile .750 gas blocks
- Rifle-length gas tubes
- 5/8×24 muzzle brakes and flash hiders
- Complete 6.5 Creedmoor upper assemblies
Shopping with Mid State Firearms makes it easy to source everything you need for a reliable, precision-built AR10 from one trusted source.
Frequently Asked Questions
Why choose a 20-inch barrel over a 24-inch barrel?
A 20-inch barrel offers an excellent balance of velocity, weight, and handling. While a 24-inch barrel may provide slightly higher muzzle velocity, the 20-inch configuration is lighter, quicker to maneuver, and still delivers excellent long-range performance with quality 6.5 Creedmoor ammunition.
What is the purpose of the gas block alignment dimple?
The factory-machined dimple is located 180° opposite the gas port and provides a precise reference point for set-screw gas blocks. This helps simplify installation, improve gas block alignment, and promote a secure fit.
What bolt carrier group does this barrel use?
Use any DPMS-pattern .308 Winchester / 6.5 Creedmoor bolt carrier group, as both cartridges share the same bolt face dimensions.
Is a 1:8 twist good for hunting and match ammunition?
Yes. A 1:8 twist is widely considered the ideal choice for stabilizing the broad range of popular 6.5 Creedmoor hunting and match projectiles, from lighter hunting bullets to heavy, high-BC match loads.
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sound of freedom – This was a great set up. I loved being able to customize the set up. Only issue I had was my own fault as a newb to building these. I used a heavy barrel in a slim hand guard. It makes adding attachments tough with clearances. Hoping someday to also get an AR10 from here.