CMMG AR-15 Barrel & BCG Kit - 8" - 5.7x28mm - Radial Delayed Blowback
6 Magazines Per Order: Due to extreme volume, we are limiting sales of magazines to 6 per customer order. This applies to individual and bundled magazines. AT3 reserves the right to cancel any order over the 6 magazine limit.
- Free standard shipping on orders $139+ details
- 90-day no-hassle returns policy
- Backed by the CMMG Warranty! what it covers
Product description
Build a 5.7×28 AR Around CMMG’s Radial Delayed Blowback System
Features
- 8″ barrel chambered in 5.7x28mm
- Includes matching CMMG 5.7x28mm Radial Delayed Blowback bolt carrier group
- Radial Delayed Blowback system reduces bolt carrier mass and felt recoil compared to traditional straight blowback systems
- Designed for assembly into a Mk4 or mil-spec AR-15 upper receiver
- Compatible with CMMG Mk57 lowers or standard Mk4/AR-15 lowers using CMMG 5.7 AR Conversion Magazines
- 4140 chrome moly barrel with salt bath nitride finish
- 1:9 twist rate with 1/2×28 muzzle threads
- No gas block or gas tube required
The CMMG 8″ 5.7x28mm Barrel and BCG Kit provides the core components for converting a compatible AR-15-pattern setup to CMMG’s Radial Delayed Blowback operating system. The matched barrel and BCG eliminate the conventional gas system while retaining AR-style controls and allowing use with either a Mk57 lower or a standard AR-15 lower equipped with CMMG 5.7 AR Conversion Magazines.
Note: The included Radial Delayed Blowback BCG requires a compatible CMMG RDB barrel extension and is not compatible with conventional AR barrel extensions.
Specifications
- Brand: CMMG
- MPN: 57D88C3
- Caliber: 5.7x28mm
- Operating System: Radial Delayed Blowback
- Barrel Length: 8″
- Barrel Profile: MT
- Twist Rate: 1:9
- Barrel Material: 4140 Chrome Moly Steel
- Barrel Finish: Salt Bath Nitride
- Muzzle Thread: 1/2×28
- Gas Port: None
- Gas Block: None
- Upper Receiver Fit: Mk4 / Mil-Spec AR-15
- Lower Compatibility: CMMG Mk57 or Mk4 / Mil-Spec AR-15 with CMMG 5.7 AR Conversion Magazines
What’s Included
- 1x CMMG 8″ 5.7x28mm Radial Delayed Blowback Barrel
- 1x CMMG 5.7x28mm Radial Delayed Blowback Bolt Carrier Group
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Warranty & returns
Backed by the CMMG Warranty!
CMMG Warranty
Seller warrants to Buyer that for a period of 6 months from the Delivery Date, all Goods will be:
- Free from any defects in workmanship, material, and design
- Conform to applicable specifications[, drawings, designs, samples and other requirements specified by Buyer]
- Fit for their intended purpose and operate as intended
- Merchantable
- Free and clear of all liens, security interests or other encumbrances
- Not infringe or misappropriate any third party’s patent or other intellectual property rights.
Inspection and Rejection of Nonconforming Goods
The Buyer has the right to inspect the Goods for a period of thirty (30) days after the Delivery Date. Buyer, at its sole option, may inspect all or a sample of the Goods and may reject all or any portion of the Goods if it determines the Goods are non-conforming or defective.
If Buyer rejects any portion of the Goods, Buyer has the right, effective upon written notice to Seller, to:
- Rescind the Order in its entirety
- Accept the Goods at a reasonably reduced price
- Reject the Goods and require replacement of the rejected Goods.
NOTES:
If Buyer requires replacement of the Goods, Seller shall, at its expense, promptly/within 30 days replace the nonconforming Goods and pay for all related expenses, including, but not limited to, transportation charges for the return of the defective goods and the delivery of replacement Goods.
If Seller fails to timely deliver replacement Goods, Buyer may replace them with goods from a third party and charge Seller the cost thereof and terminate this Order for cause pursuant to Section 20.
Any inspection or other action by Buyer under this Section shall not reduce or otherwise affect Seller’s obligations under the Order, and Buyer shall have the right to conduct further inspections after Seller has carried out its remedial actions.
Disclaimer: Manufacturer’s warranty is subject to change without prior notice.
90-day no-hassle returns
The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.
If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.