Brand: CMMG
Model: Resolute
Caliber: 300 Blackout
Platform: Mk4
Barrel: 16.1", 4140CM, SB
Color: Armor Black
Finish: Cerakote
Gas System: Carbine Length, Direct Impingement
Muzzle Device: CMMG Zeroed Muzzle Brake
Muzzle Thread: 5/8-24
Twist: 1:7
Receiver: Billet 6061 T6 Aluminum
Handguard: CMMG EML 15"
Attachment Style: M-Lok
BCG: Yes
Charging Handle: Zeroed Ambi Charging Handle

Features

CMMG RESOLUTE .300 Blackout Upper – Versatile, Suppressor-Ready Performance Originally developed for subsonic and suppressed use, .300 AAC Blackout has become a highly adaptable caliber—ideal for hunting, personal defense, and target shooting. The CMMG RESOLUTE Upper Group in .300 Blackout is the perfect way to complete your next carbine build, designed for seamless compatibility with any standard AR-15 lower receiver. Each upper comes complete with a bolt carrier group and a suite of CMMG’s Zeroed components, including an ambidextrous charging handle, polymer dust cover, and .308-caliber muzzle brake—delivering out-of-the-box performance and customization.

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Shipping Restrictions

It is the customer’s responsibility for understanding state laws regarding all purchases made. For a comprehensive list of all Shipping Restrictions, please refer to our Shipping Restrictions By State Page found Here.

All NFA Rules Apply

These items are controlled by the U.S. Government and authorized for export only to the country of ultimate destination for use by the ultimate consignee or end-user(s) herein identified. They may not be resold, transferred, or otherwise disposed of, to any other country or to any person other than the authorized ultimate consignee or end-user(s), either in their original form or after being incorporated into other items, without first obtaining approval from the U.S. government or as otherwise authorized by U.S. law and regulations.

Local Law Compliance

Certain firearm parts and accessories, including AR-style upper receivers, are subject to complex and frequently changing federal, state, and local laws and regulations. While an upper receiver may be lawfully sold and shipped as a component, the legality of possessing, assembling, configuring, or using an upper receiver in certain states (e.g., California, Washington State) and localities depends on how it is assembled, combined with other components, and ultimately used. You are solely responsible for ensuring that any assembly, configuration, possession, or use complies with all federal, state, and local laws, including any so-called “assault weapon” bans and short-barreled rifle restrictions. We do not provide legal advice and are not responsible for unlawful configurations or uses.