Description

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

The FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 represents the latest evolution in precision trigger engineering from Rare Breed. Designed specifically for the HK MR223 and HK MR556 platform, this drop-in trigger system delivers a distinctive single-stage pull with a forced-reset mechanism that allows the shooter to maintain a consistent finger position through the firing cycle. Unlike standard triggers, the FRT-MR3 utilizes a three-position selector that provides safe, semi-automatic, and forced-reset functionality, giving the operator direct control over the trigger’s mechanical behavior. This unit is machined from heat-treated steel components with a flat, serrated trigger shoe that reduces finger slip and promotes repeatable placement. The entire assembly is housed in a reinforced polymer cassette that simplifies installation without the need for trigger work or aftermarket pins. Every FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 is tested at the factory to ensure reliable reset timing and consistent pull weight across all three selector positions.

Overview

The FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 is a direct replacement for the factory trigger group in HK-pattern rifles chambered in 5.56 NATO. The flat shoe design reduces overall trigger reach by approximately 0.10 inches compared to curved triggers, which benefits shooters with shorter fingers or those using armored gloves. The forced-reset mechanism uses a proprietary sear geometry that automatically resets the trigger forward after each shot, allowing the shooter to maintain contact with the trigger face throughout the reset cycle. This mechanical design does not alter the rifle’s semi-automatic fire rate capabilities but rather changes how the trigger interacts with the shooter’s finger during rapid follow-up shots. The three-position selector is clearly marked and provides positive detent engagement at each stop. All internal components are coated with a dry-film lubricant that functions across a temperature range of -20 to 160 degrees Fahrenheit.

Features & Specs

• Flat, serrated trigger shoe machined from 4140 steel with a black nitride finish; single-stage pull weight factory set at 4.5 to 5.5 pounds with less than 0.5 pounds of overtravel after reset
• Three-position selector: safe (rear), semi-automatic (center), forced-reset (forward); each position uses a hardened steel detent spring rated for 25,000 cycles
• Drop-in cassette design compatible with HK MR223 and MR556 lower receivers; includes all necessary pins and springs; no permanent modification to the firearm required

Additional specifications include a trigger travel distance of 0.120 inches from rest to sear release, with a reset travel of 0.080 inches in the forced-reset position. The hammer is constructed from S7 tool steel and includes a full-face strike surface to ensure reliable primer ignition across various ammunition brands. The entire trigger group weighs 2.4 ounces and measures 2.75 inches in length. Rare Breed tests each unit with a minimum of 200 dry-fire cycles and 50 live-fire rounds before packaging.

Who It’s For

This FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 is intended for experienced shooters who understand the mechanical operation of forced-reset trigger systems and require a trigger that maintains consistent performance under sustained firing schedules. It is suitable for competitive shooters participating in two-gun or three-gun matches where rapid target transitions demand a predictable reset point. Law enforcement and military personnel who train with MR223 or MR556 platform rifles may find the flat shoe geometry advantageous for maintaining sight alignment during high-round-count drills. The trigger is not recommended for new shooters who have not yet developed a disciplined trigger control technique, as the forced-reset mechanism requires deliberate finger management to operate safely. Users must verify local and state regulations regarding forced-reset trigger ownership before purchase, as some jurisdictions restrict or prohibit these devices.

Shipping & FFL

This product is a firearm component that may be classified as a regulated part depending on your state and local laws. By purchasing this FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556, you acknowledge that you are responsible for complying with all applicable federal, state, and local regulations. Some jurisdictions require this trigger to be shipped to a Federal Firearms License (FFL) dealer for transfer. We will ship to your chosen FFL dealer if required by law. If an FFL transfer is not mandated in your state, we will ship directly to your verified billing address. Please include your FFL dealer’s information at checkout if applicable. We cannot ship to P.O. boxes, APO/FPO addresses, or locations where forced-reset triggers are prohibited. All shipments require an adult signature upon delivery. Allow 3-5 business days for order processing before shipment.