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The CMMG Barrel Sub-Assembly is a high-quality option for building or refreshing a custom AR-15 upper group. Chambered in .300 Blackout with a 16.1-inch 4140 chrome molybdenum steel barrel and a durable black nitride (salt bath nitride) finish, it's designed for reliable performance and long service life. This barrel sub-assembly includes a properly installed M4 barrel extension and is properly headspaced to help streamline your build.
Product Highlights
- 16.1 in .300 Blackout AR-15 barrel sub-assembly for custom upper builds and replacements
- 4140 chrome molybdenum steel construction with black nitride (salt bath nitride) finish inside and out
- Medium taper barrel profile with carbine-length gas system for balanced handling
- Threaded 5/8-24 muzzle and .750 in gas journal to fit common muzzle devices and gas blocks
- Properly installed M4 barrel extension; factory headspaced for simplified assembly
Specs
- Brand: CMMG
- Manufacturer Part Number: 30D120A
- UPC: 815835016238
- Caliber/Chamber: .300 Blackout (.300 AAC Blackout)
- Barrel Length: 16.1 in (16.10 in)
- Material: 4140 Chrome Molybdenum (Chromoly) Steel
- Finish: Black Nitride / Salt Bath Nitride (inside and out)
- Barrel Profile: Medium Taper
- Gas System Length: Carbine
- Gas Block Journal Diameter: .750 in (0.75 in)
- Twist Rate: 1:7
- Muzzle Threads: 5/8-24
- Barrel Extension: M4 (installed)
- Headspaced: Yes (properly headspaced)
- Weight: 1.5 lb
Specifications
- Manufacturer:
- Cmmg
- Category:
- barrel
- Caliber:
- .300 AAC Blackout
- Platforms:
- AR-15
- Interfaces:
- Muzzle thread: 5/8-24
- Weight:
- 24 oz (1.50 lbs)
- Length:
- 16.1"
- Estimated velocity:
- 1,900-2,450 fps
- UPC:
- 8228963418234
- MPN:
- 30D120A
- Required Component:
- Yes
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