The Mustang Armament Chesty Series is the flagship line of duty-grade fighting firearms, built for shooters who want uncompromising reliability, premium craftsmanship and suppressor-optimized performance. This compact 8" .300 AAC Blackout build wears a Distressed Grey Cerakote over an exclusive Betsy Ross billet receiver set with a matching 7" billet handguard. A proprietary cold hammer forged barrel, a KynSHOT hydraulic recoil buffer and a LAW Tactical Gen-3 folding adapter make it rugged, exceptionally well balanced and easy to store. Topping it is a premium fighting package headlined by an EOTech EXPS2-2 holographic weapon sight with a 3X magnifier on a riser.

The platform starts on Mustang Armament's exclusive Betsy Ross billet receiver set in a striking Distressed Grey Cerakote, matched to a 7" billet handguard in the same finish. Timeless American heritage meets cutting-edge engineering here, in a compact and rugged package purpose-built for home defense, personal protection, vehicle deployment and suppressed shooting.

At the heart of the system is Mustang Armament's proprietary 8" Cold Hammer Forged Duty Precision Taper barrel, cut from premium steel with 5R rifling and a 1:7 twist, HPT/MPI inspected and run on a pistol-length gas system. Combined with a premium gas block and a Plan B quick detach muzzle device, the barrel was engineered specifically to get the most out of the .300 AAC Blackout cartridge, delivering outstanding reliability with both supersonic and subsonic ammunition.

The operating system uses an Enhanced DLC Sand Cut bolt carrier group, fully HPT/MPI inspected, with a Next Level Armament gas-busting ambidextrous charging handle. Together they promote exceptional reliability under adverse conditions while significantly reducing gas blowback when running suppressed.

Fire control is the proven Rise Armament RA-434 single-stage performance trigger, breaking crisply at 3.5 pounds with a lightning-fast reset. It is matched to the Rise Armament ambidextrous safety selector, so the controls stay intuitive for right- and left-handed shooters alike.

Premium enhancements run throughout: a Geissele magazine release, a Driven Arms Co. performance grip, PWS enhanced receiver pins, an enhanced bolt catch, an Emissary Development hand stop, an Emissary Development foregrip, rail scales and integrated QD sling attachment points.

The recoil system pairs the SB Tactical SBA5 brace, a premium receiver extension and a ratcheting castle nut with a KynSHOT hydraulic recoil buffer, creating an exceptionally smooth impulse and improving reliability across a wide range of ammunition and suppressor configurations. This build has been optimized specifically for modern low-back-pressure suppressors such as the Exigent Defense Fireteam 762, the Irregular Design Group Hesychia SIX-H and other Plan B-compatible systems, though no suppressor is included here. The Duty Precision Taper barrel, tuned gas system and hydraulic recoil assembly work together for reduced recoil, lower gas blowback, faster follow-up shots and exceptional overall shootability.

The fighting package is led by the EOTech EXPS2-2 holographic weapon sight with a 3X magnifier mounted on a riser, backed by a Streamlight 1,000-lumen weapon light on a remote tapeswitch. A LAW Tactical Gen-3 folding adapter rounds it out, letting the firearm be transported in an incredibly compact configuration without sacrificing durability or reliability.

The series is named in honor of LtGen Lewis "Chesty" Puller, one of the most decorated Marines in American history and a fellow Mustang Marine, and every build in it is meant to carry the toughness, leadership and fighting spirit for which he is remembered.

Specifications

• Caliber: .300 AAC Blackout
• Barrel Length: 8"
• Barrel Type: Mustang CHF Duty Precision Taper, 5R Rifling, 1:7 Twist, HPT/MPI Tested
• Gas System: Pistol-Length
• Bolt Carrier Group: Enhanced DLC Sand Cut, HPT/MPI
• Charging Handle: NLA Gas-Busting Ambidextrous
• Trigger: Rise Armament RA-434, 3.5 lb Single-Stage
• Safety: Rise Armament Ambidextrous
• Buffer System: KynSHOT Hydraulic Recoil Buffer
• Brace: SB Tactical SBA5
• Muzzle Device: Plan B Quick Detach
• Folding Adapter: LAW Tactical Gen-3
• Sight: EOTech EXPS2-2 with 3X Magnifier
• Light: Streamlight 1,000-Lumen with Remote Tapeswitch
• Finish: Distressed Grey Cerakote
• Receiver: Custom Betsy Ross Billet Receiver Set
• Handguard: 7" billet