FRT-MR3™ (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556

Engineered specifically for the precision platform of the HK MR223 and HK MR556, the Rare Breed FRT-MR3™ (Flat) Single-Stage (3-Position) Forced Reset Trigger introduces a new level of mechanical control for the discerning shooter. This trigger unit is a direct-drop-in component that replaces the factory fire control group, offering a distinct three-position selector system. The FRT-MR3™ operates on a forced-reset principle, where the trigger blade is mechanically pushed forward after each shot, requiring the shooter to release pressure before the next cycle. This design provides a unique shooting cadence that bridges the gap between standard semi-automatic fire and rapid follow-up shots, all while maintaining a flat, smooth trigger face for consistent finger placement.

Overview

The FRT-MR3™ (Flat) is a single-stage, three-position forced reset trigger built exclusively for the HK MR223 and HK MR556 platforms. Unlike traditional triggers, this unit uses the bolt carrier group energy to reset the trigger shoe, creating a tactile and audible reset that allows for faster, more controlled shot strings. The three-position selector includes Safe, Semi-Automatic, and the Forced Reset setting. The flat trigger shoe reduces over-travel and provides a consistent pull weight across all positions. Each unit is machined from billet steel and hard-coat anodized for corrosion resistance, meeting the rigorous standards expected by Florida shooters operating in humid or coastal environments.

Features & Specs

• Trigger Mechanism: Single-stage, forced-reset design with a mechanical push-forward function. The trigger must be fully released between shots to engage the reset, preventing run-away fire. Pull weight is factory-set at 4.5 to 5.5 pounds with a crisp break and minimal creep.
• Selector Positions: Three-position safety selector (Safe, Semi, Forced Reset). The forced reset position uses a unique cam geometry that interacts with the hammer and bolt carrier, ensuring the trigger resets only when the bolt is fully forward and locked.
• Materials & Construction: CNC-machined from 4140 steel with a MIL-SPEC hard-coat anodized finish. The flat trigger shoe is serrated at 20 lines per inch for positive traction. Includes a hardened steel disconnector and a nickel-Teflon coated hammer for reduced friction.
• Compatibility: Drop-in fit for HK MR223 and HK MR556 rifles. Does not require permanent modification to the lower receiver. Uses factory hammer and trigger pins. Not compatible with AR-15 or other HK pattern rifles without specific bolt carrier profiles.
• Dimensions: Overall trigger width: 0.250 inches. Shoe length: 1.125 inches. Weight: 2.8 ounces. Operating temperature range: -20°F to 160°F.

Who It’s For

This forced reset trigger is designed for experienced shooters who own an HK MR223 or HK MR556 and desire a higher degree of mechanical control over their firing cadence. It is suitable for competitive shooters in disciplines that allow forced reset triggers, such as certain 2-Gun and 3-Gun matches, as well as for training applications where rapid, controlled follow-up shots are practiced. The FRT-MR3™ (Flat) is also appropriate for collectors and enthusiasts who study firearm mechanics and want to understand the engineering behind the forced-reset action. This product is not intended for general recreational plinking without prior familiarity with the reset technique. Only users who can safely demonstrate trigger discipline and manual cycling awareness should install this component.

Shipping & FFL

• Availability: This FRT-MR3™ (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 is in stock and ready to ship. Orders are processed within one business day.
• Shipping: We ship to all addresses in Florida and throughout the United States where legal. Standard shipping is via UPS Ground or FedEx with tracking provided. Expedited options are available at checkout.
• FFL Transfer Disclaimer: This product is a firearm component and is not classified as a firearm by the ATF. It does not require transfer through a Federal Firearms License (FFL) dealer for purchase or shipment. However, the end user must comply with all applicable federal, state, and local laws. For Florida residents, no additional state permit is required for this trigger component. It is the buyer’s responsibility to ensure compliance with any local ordinances regarding trigger mechanisms. Rare Breed Triggers, LLC recommends consulting with a legal professional before installation if you have any questions regarding compliance.