Noveske and Irregular Defense Collaborate on Limited-Run 6mm ARC Chainsaw SBR

Noveske and Irregular Defense have joined forces to collaborate on a short-barrel rifle build in 6mm ARC. The limited-edition Chainsaw is a 12.5-inch build equipped with Irregular Defense accessories designed to improve the rifle’s quality of life when shooting. Let’s break down the components that make up this collaborative build.

Upper Receiver and Bolt Carrier Group

The upper receiver is forged from 7075-T6 aluminum and finished with a Type III hardcoat anodizing, followed by an FDE Cerakote topcoat. This multi-layer finishing process helps promote long-term durability while improving the longevity of the Cerakote finish.

The engine that drives this Chainsaw build is a phosphate-coated bolt carrier that is full-auto capable and features a chrome-lined bore and gas key.

The bolt itself is Noveske’s DLC-coated 6mm ARC / 6.5 Grendel bolt, manufactured from SAE 9310 heat-treated steel for added strength and durability.

Barrel and Gas System

At the heart of the rifle is a 12.5-inch Noveske barrel made from 416R stainless steel, chambered in 6mm ARC with a 1:7 twist rate. The barrel utilizes a mid-length gas system paired with a pinned gas block for reliable cycling.

Additional barrel features include:

• M4 barrel extension

• Hand-polished feed ramps

• Polished match-grade chamber

These refinements are intended to promote reliable feeding while maintaining the accuracy standards Noveske rifles are known for.

Noveske’s Serialized Barrel Philosophy

Attention to detail has long been a core principle for Noveske. Each barrel used in the Chainsaw series is individually serialized, a practice intended to maintain strict standards of quality control, accuracy verification, and traceability throughout the manufacturing process.

Handguard and Irregular Defense Accessories

Surrounding the barrel is Noveske’s 4th Generation NSR 10.75-inch M-LOK handguard. M-LOK slots are positioned at 45-degree intervals, while a 1913 Picatinny rail runs along the top for weapon lights or laser aiming modules (LAMs).

This collaborative build also includes several Irregular Defense accessories:

• Modular Rail Covers (MRC) – help protect the shooter’s hands from heat generated during extended firing.

• Modular Hand Stop (MHS) – provides a consistent reference point for the support hand.

• Modular Barricade Stop (MBS) – allows shooters to brace the rifle against barriers for improved stability.

Completing the upper assembly is Irregular Defense’s HESYCHIA Hybrid flash hider, threaded 5/8×24.

Lower Receiver and Fire Control

The lower receiver mirrors the construction of the upper, forged from 7075-T6 aluminum with a Type III hardcoat anodizing and finished in FDE Cerakote. The receiver also features an Irregular Defense roll mark, highlighting the collaborative nature of the build.

This Chainsaw build features an Geissele Automatics SSA-E trigger, which provides a clean and crisp break at 4.5-pounds, one of the best enhanced mil-spec triggers on the market.

Additional lower receiver components include:

• Mil-spec six-position buffer system

• B5 Systems Bravo stock

• Irregular Defense cheek riser

• Irregular Defense Special-K grip

Together, these components round out the rifle’s ergonomics while maintaining a lightweight and functional 6mm ARC build. 

Price & Availability 

The Chainsaw 12.5” 6mm ARC SBR represents a focused collaboration between Noveske and Irregular Defense, blending Noveske’s reputation for precision manufacturing with Irregular Defense’s ergonomic accessory ecosystem. The result is a compact rifle platform designed for both performance and shooter comfort. With a retail price of $2,875, the rifle is offered as a limited-edition build, meaning availability will likely be restricted to existing inventory. For enthusiasts interested in the platform, the Chainsaw series will be available while supplies last.