Description

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

Designed and manufactured by Rare Breed, the FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 represents a precision-engineered upgrade for the HK-platform semi-automatic rifle. This trigger system is built to the exacting tolerances required for the MR223 and MR556 receivers, delivering a distinct forced-reset mechanism that allows the shooter to maintain consistent, rapid follow-up shots while retaining full semi-automatic compliance. The flat trigger shoe profile provides a consistent purchase point for the trigger finger, reducing variability during high-speed manipulation. This is not a drop-in modification for standard AR-15 platforms; it is specifically machined and tuned for the proprietary fire control group geometry of the HK MR223 and MR556.

Overview

The FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & MR556 is a three-position select-fire trigger system. Position one is safe. Position two is semi-automatic (standard single-shot per trigger pull). Position three activates the forced-reset function, where the trigger forward assist mechanism resets the trigger shoe forward after each shot, enabling the shooter to ride the reset and fire again with minimal additional rearward movement. The trigger pull weight is set at the factory to a consistent 5.5 pounds with a crisp, single-stage break. The flat shoe is machined from 7075-T6 aluminum and finished with a MIL-SPEC hardcoat anodize for extended service life in adverse conditions. This trigger is designed exclusively for the HK MR223 and HK MR556 platforms and will not function correctly in standard AR-15 lower receivers due to differences in the hammer pin location and trigger pocket depth.

Features & Specs

• Mechanism: Three-position select-fire with forced-reset function (Safe, Semi-Automatic, Forced Reset). The forced-reset mode uses a mechanical forward assist spring to push the trigger shoe forward immediately after the hammer drop, allowing the shooter to release and re-engage the trigger with a short, consistent stroke.
• Construction: Flat trigger shoe made from 7075-T6 aluminum with MIL-SPEC Type III hardcoat anodize. Internal components are machined from Carpenter 158 steel and heat-treated to military specification for wear resistance and dimensional stability under sustained firing schedules.
• Compatibility: Specifically designed for the HK MR223 (European market) and HK MR556 (US market) variants. Not compatible with standard AR-15, AR-10, or other HK-pattern rifles. Requires factory-spec HK trigger group pins (0.154 inch diameter) and standard HK hammer spring.

Who It’s For

This trigger is intended for the HK MR223 and MR556 owner who requires a precise, repeatable trigger system for competitive shooting, training, or defensive application. The forced-reset function is particularly useful for shooters who want to maximize split times without converting to a full-automatic platform. The flat shoe profile reduces trigger finger travel distance and provides a consistent tactile reference point, which is advantageous for shooters with longer fingers or those using gloves. The FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & MR556 is also suitable for HK-pattern rifles used in law enforcement training or duty roles where rapid, controlled fire is necessary. It is not a novelty item; it is a functional upgrade for shooters who understand the forced-reset mechanism and can safely manipulate it under stress.

Shipping & FFL

This product is classified as a firearm component and is regulated by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). The FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 will only be shipped to a Federal Firearms License (FFL) holder where required by applicable state and federal laws. Customers must provide a valid FFL copy at the time of order. Some states and municipalities have restrictions on the sale, possession, or use of forced-reset triggers. It is the sole responsibility of the purchaser to verify that this trigger is legal to own and operate in their jurisdiction before placing an order. All sales are final. No returns or exchanges on installed or modified trigger components. Standard shipping rates apply; expedited shipping is available upon request.