The YHM Resonator .300 BLK Integrally Suppressed Upper Receiver Group pairs a 9.1" .300 AAC Blackout barrel with a permanently attached Resonator suppressor for a streamlined, one-stamp solution. A lightweight MR7 M-LOK handguard surrounds the integral can, while the YHM Mil-Spec A3 flat-top upper provides a solid foundation for your preferred optics and accessories. A specially designed low-profile gas block and black plated gas tube are tuned to reduce blowback and maintain smooth cycling, and the system is full-auto rated with a decibel rating of 127 dB using .300 BLK subsonic ammunition.

This integrally suppressed upper is ideal for shooters who want a compact, hearing-friendly .300 Blackout setup for range use, training, or hunting where sound reduction is a priority. With an overall barrel and suppressor length of just over 16", it keeps handling familiar while simplifying NFA paperwork to a single tax stamp. Built around Yankee Hill Machine’s proven Resonator suppressor construction of 17-4 PH stainless steel with a Cobalt-6 blast baffle, it reflects the company’s focus on durability, practical design, and consistent performance.

Key Features:

• Manufacturer: Yankee Hill Machine
• Model: Resonator .300 BLK Integrally Suppressed Upper Receiver Group
• Caliber: .300 AAC Blackout
• Barrel Length: 9.1"
• Length: 23.5"
• Weight: 3.3 lbs
• Diameter: 1.5625"
• Decibel Rating: 127 dB with .300 BLK subsonic
• Construction: 17-4 PH Stainless Steel With Cobalt-6 Blast Baffle
• Handguard: MR7 9" M-LOK
• Upper Receiver: Flat Top A3
• Included Components: Resonator Suppressor Assembly, Handguard, Upper Receiver, Low Profile Gas Block, Black Plated Gas Tube
• Full Auto Rated: Yes