Mossberg Expands 590R Platform with New Chisel Machining Configurations

Mossberg has expanded its 590R/RM lineup with the introduction of the new 590R Chisel and 590RM Chisel pump-action shotguns. Developed in collaboration with Chisel Machining, these models pair Mossberg’s rotary-safety pump platform with a premium folding stock solution, offering improved ergonomics, compact handling, and a purpose-built setup for defensive and tactical use.

The 590R Chisel features an 18.5-inch barrel with an integrated heat shield and is equipped with a Chisel Machining folding stock mount. This configuration provides a stable shooting platform while allowing the shotgun to fold down for easier storage and transport. The receiver is finished in Flat Dark Earth Cerakote, adding corrosion resistance and a clean, modern appearance.

Built for maximum maneuverability, the 590RM Chisel is configured with an 11.5-inch barrel and a 10-round detachable magazine. Despite its compact footprint, it delivers substantial on-board capacity and fast handling in tight spaces. Like the 590R Chisel, it features the Chisel Machining folding stock mount and Flat Dark Earth Cerakote finish, maintaining a consistent look and feel across the platform.

Both models are based on Mossberg’s pistol-grip rotary-safety pump-action system, designed for positive feeding and dependable performance. The folding stock adds flexibility for vehicle use, storage, or confined environments, while still providing solid control when deployed.

Key features of the 590R/RM Chisel shotguns include:

• Ambidextrous rotary safety that can be engaged without breaking grip
• Mossberg adjustable stock with eight length-of-pull positions (12.5–16 inches), interchangeable recoil pad, and ambidextrous QD sling cups
• Chisel Machining folding stock mount
• Magpul MOE+ pistol grip
• Accu-Choke system
• Flat-profile trigger with a clean, consistent break
• Top-mounted Picatinny rail for optics
• Enlarged, beveled loading port with extended follower (590R only)
• Elongated bolt release
• E-coated internal and external receiver surfaces for added durability and smoother operation

Chisel Machining, based in California, specializes in precision-machined firearm components built for strength and real-world use. Their folding stock system on the 590R/RM Chisel reflects a focus on durability, clean industrial design, and practical performance.

With the addition of the 590R Chisel and 590RM Chisel, Mossberg continues to evolve the 590R platform with configurations aimed at shooters who want compact capability without sacrificing reliability or control.

More information on these new models is available at Mossberg’s website.

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