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CMMG, Inc 308 Win Barrel Sub-Assembly Up to 10% Off w/ Free S&H — 3 models

CMMG, Inc CMM MK3 Medium Taper Profile Barrel Sub-Assembly 416SS, .308 Winchester, 12.5in, 5/8-24 Threads, Salt Bath Nitride Finish, 38D920A
CMMG, Inc Barrel Sub-Assembly, 18.0in. HT 416SS, 308 Win 38DCC0A
CMMG, Inc Barrel Sub-Assembly, .308 Winchester, 20 inch, Medium Taper, 416SS, SBN, Black, 38DDA0C
CMMG, Inc CMM MK3 Medium Taper Profile Barrel Sub-Assembly 416SS, .308 Winchester, 12.5in, 5/8-24 Threads, Salt Bath Nitride Finish, 38D920A
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CMMG, Inc CMM MK3 Medium Taper Profile Barrel Sub-Assembly 416SS, .308 Winchester, 12.5in, 5/8-24 Threads, Salt Bath Nitride Finish, 38D920A
CMMG, Inc Barrel Sub-Assembly, 18.0in. HT 416SS, 308 Win 38DCC0A
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CMMG, Inc Barrel Sub-Assembly, 18.0in. HT 416SS, 308 Win 38DCC0A
CMMG, Inc Barrel Sub-Assembly, .308 Winchester, 20 inch, Medium Taper, 416SS, SBN, Black, 38DDA0C
3 of 3 images
CMMG, Inc Barrel Sub-Assembly, .308 Winchester, 20 inch, Medium Taper, 416SS, SBN, Black, 38DDA0C

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Questions & Answers
What is the twist rate for both .308 cal barrels?

I believe that 1:10 and 1:12 are the most common twist rates for .308 caliber barrel.

by JD, Verified Owner, February 11, 2021
See 2 More Answers
How much does the medium profile 20" barrel weigh? Expert Answer

CMMG does not state the weight of the CMMG, Inc 308 Win Barrel Sub-Assembly. I recommend contacting CMMG for that information.

by Hunter, Gear Expert, April 13, 2023
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Customer Reviews
Most Recent Reviews
Good, accurate shorty .308 barrel. by JB83, Verified Owner, July 10, 2025
I have heard both bad and good about CMMG barrels and I only have this one to test. That said, I have liked it so far. Seems accurate. Have yet to bench zero... Came pre-dimpled for the gas block. I love that it has mid-length gas... that's going to ...
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Read 1 Review
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Product Info for CMMG, Inc 308 Win Barrel Sub-Assembly

This CMMG 308 Win Barrel Sub-Assembly is the perfect raw material to craft your custom MK3 upper group. CMMG constructed these Rifle Barrels with a properly installed barrel extension so that you can save even more time by avoiding the extra hassle of installing a barrel after the fact. This CMMG 308 Rifle Barrel Sub-Assembly comes headspaced for a reliable build, and the 5/8x24 threads allow for the installation of a variety of accessories you may need down the road. Make sure you pick up a CMMG 308 Barrel Sub-Assembly w/ Extension if you're looking to build your own MK3 upper group.image

Specifications for CMMG, Inc 308 Win Barrel Sub-Assembly:

Manufacturer: CMMG
Caliber: .308 Winchester
Barrel Twist Rate: 1-10
Flutes: No
Gun Model: AR-10
Condition: New
Firearms Threads Per Inch: 5/8x24

Package Contents:

  • CMMG, Inc 308 Win Barrel Sub-Assembly

What firearm models does the manufacturer say CMMG, Inc 308 Win Barrel Sub-Assembly is compatible with?

The manufacturer says that CMMG, Inc 308 Win Barrel Sub-Assembly is compatible with AR-10

CMMG, Inc 308 Win Barrel Sub-Assembly Orderable Models

List of Orderable Models

  • CMMG, Inc Barrel Sub-Assembly, Mediun Taper Profile, 308 Win, 12.5in, 416SS, Salt Bath Nitride, 38D920A , MPN: 38D920A , UPC: 815835016351 , Code: 2CM-ATB-308WINBRL-38D920A
  • CMMG, Inc Barrel Sub-Assembly, Heavy Taper, 308 Win, 18in, 416SS, 38DCC0A , MPN: 38DCC0A , UPC: 815835016320 , Code: 2CM-ATB-308WINBRL-38DCC0A
  • CMMG, Inc Barrel Sub-Assembly, Medium Taper, 308 Win, 20in, 416SS, Salt Bath Nitride, 38DDA0C , MPN: 38DDA0C , UPC: 816422026821 , Code: 2CM-ATB-308WINBRL-38DDA0C

CMMG, Inc 308 Win Barrel Sub-Assembly Unavailable & Discontinued Models

List of Unorderable Models

  • DEMO, CMMG, Inc Barrel Sub-Assembly, Heavy Taper, 308 Win, 18in, 416SS, 38DCC0A , MPN: 38DCC0A-DEMO , Code: 2CM-ATB-308WINBRL-38DCC0A-DEMO
  • CMMG, Inc Barrel Sub-Assembly, Medium Taper, 308 Win, 16.1in, 416SS, Salt Bath Nitride, 38DEA7A , MPN: 38DEA7A , UPC: 815835016337 , Code: 2CM-ATB-308WINBRL-38DEA7A
  • DEMO, CMMG, Inc Barrel Sub-Assembly, Medium Taper, 308 Win, 16.1in, 416SS, Salt Bath Nitride, 38DEA7A , MPN: 38DEA7A-DEMO , Code: 2CM-ATB-308WINBRL-38DEA7A-DEMO
  • DEMO, CMMG, Inc Barrel Sub-Assembly, Mediun Taper Profile, 308 Win, 12.5in, 416SS, Salt Bath Nitride, 38D920A , MPN: 38D920A-DEMO , Code: 2CM-ATB-308WINBRL-38D920A-DEMO
  • CMMG, Inc Barrel Sub-Assembly, Heavy Taper, 308 Win, 24in, 416SS, Salt Bath Nitride, 38D4B0C , MPN: 38D4B0C , UPC: 816422026838 , Code: 2CM-ATB-308WINBRL-38D4B0C
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Last updated 2026-07-29 UTC.