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
New: Fix It Sticks Armorer’s Punch Toolkit
Fix It Sticks pairs a new magnetic-socket hammer with 24 punches in a portable kit aimed at competition shooters, armorers and gunsmiths who work on guns away from the bench.
Champions Old And New: 1989 National Matches
The 1989 National Matches featured new metric targets, a record-setting U.S. Pershing Team victory, repeat champions and breakthrough performances across all disciplines.
NRA America’s Rifle Challenge: Kyle Lamb’s Position-by-Position Guide to the ARC Barricade
Kyle Lamb covers six positions on the NRA ARC barricade with practical tips on stability, transitions and rifle placement.
Collegiate Rifle: Akron Closes Season with Record Performance at GARC Championship
Akron set a school smallbore record of 2346 and finished fifth at the 2026 GARC Championship at West Point, just one point behind Army.
Cameron Hicks Takes FITASC and EZGO Shootout Titles at 2026 Seminole Cup
Cameron Hicks wins FITASC HOA over 205 shooters at the 2026 Seminole Cup, matching his father’s FITASC victory from 2003.
Rhode Island Wins Inaugural National Intercollegiate Rifle League Title
Rhode Island wins inaugural Scopos Intercollegiate Rifle League team title while Georgia Military College’s MacKenzie Sookhoo sweeps all eight individual competitions.
SECTIONS
IN THE SPOTLIGHT
EXPLORE MORE NRA PUBLICATIONS
