MasterPiece Arms (MPA) has introduced a new product line, the MPA Rapid Adjustment Technology (RAT) System. This system enables MPA Chassis users to quickly adjust bipod, tripod and barricade stops on the fly. The RAT system is composed of the Base, Harris Adaptor, Dovetail Adaptor Plate, Picatinny Rail Adaptor and Magnetospeed System.
Coming in at a svelte one pound, the lightweight RAT Base (MSRP $70) can attach a variety of accessories to the 1.5″ Dovetail Cut on the MPA BA Chassis System. A pocket is machined into the bottom that includes holes designed to accept a series of accessories that will attach to the Base, allowing the shooter to utilize the RAT System. It attaches to the RAT Dovetail Adaptor Plate mounted to the MPA Spigot Mount. Additionally, an Atlas Bipod can also mount directly to the RAT Base.
The RAT Dovetail Adaptor Plate (MSRP $30) attaches to the Spigot Mount on the MPA BA Chassis System and allows the shooter to run the RAT System and all the accessories on both the chassis body and the Spigot Mount. It’s also needed to run the Magnetospeed Adaptor on the MPA BA Chassis. Installation consists of simply removing the existing Picatinny rail from the Spigot Mount, and attaching the RAT Dovetail Adaptor Plate.
The RAT Harris Adaptor (MSRP $90) provides an attachment method for the Harris Bipod to the 1.5″ Dovetail Cut on the MPA BA Chassis System, and also the RAT Dovetail Plate (Spigot Mount). It is designed to replace the sling stud attachment plate on a Harris Bipod.
The RAT Picatinny Rail Adaptor (MSRP $90) is designed to provide an attachment method for items that interface with a Picatinny rail. This connects to the 1.5” Dovetail Cut on the MPA BA Chassis System, as well as the RAT Dovetail Plate (Spigot Mount).
The RAT Magnetospeed Adaptor (MSRP $90) is designed to provide an attachment method of a Magnetospeed V2 or V3 to the RAT Dovetail Adaptor Plate (Spigot Mount) on the MPA BA Chassis. Shooters can attach the Magnetospeed to the rifle without contacting the barrel. This eliminates any point of impact shift concerns when the shooter is gathering data on velocity. The system includes the RAT Base, Magnetospeed Adaptor Block, and attachment rod and thumb wheel. A Spigot Mount and RAT Dovetail Adaptor Plate are required to attach to the chassis.
New: MasterPiece Arms Rapid Adjustment Technology
More like this from around the NRA
Latest
Richard Heinie: USPSA Original, 1911 Single Stack Maestro Still Building at 83
Richard Heinie, USPSA charter member and premier 1911 gunsmith, co-founded the Single Stack Classic and still builds custom pistols at 83.
New: Staccato HD P4X
Staccato’s new HD P4X is a full-size, steel-frame duty pistol with an integral compensator, 18-round capacity and Glock-pattern magazine compatibility.
2026 NRA National Pistol Championship Team Results
USAMU Blue posted the week’s top team aggregate while Zero Lapua defended its open club title at the 2026 NRA Pistol Nationals.
Jon Shue Wins Fourth Consecutive NRA National Pistol Title
Jon Shue claims his fourth consecutive NRA Precision Pistol national title with a 2659-156X Grand Aggregate at the Cardinal Shooting Center.
Vintage USPSA Scoring Overlays Reveal A Forgotten Rule
These vintage USPSA/NROI scoring overlays lack a .40-cal. gauge and feature mysterious “eyebrow” markings tied to a long-retired scoring rule.
Wilson Combat Marks 250 Years of American Independence with Limited Edition 1911 Series
Wilson Combat’s America 250th Limited Edition 1911 Series celebrates the Semiquincentennial with commemorative engraving, including 25 pistols hand-engraved by Wayne D’Angelo.
Interests
SECTIONS
IN THE SPOTLIGHT
EXPLORE MORE NRA PUBLICATIONS
