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

If you are building or upgrading an HK-pattern rifle chambered in 5.56, the trigger system you choose directly affects how the rifle performs under rapid fire. The FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 is a drop-in assembly engineered specifically for these platforms. It uses a three-position selector and a flat-faced trigger shoe to give you a crisp, predictable break while maintaining the forced-reset cycle that experienced shooters have come to rely on. This is not a gimmick; it is a functional upgrade for those who understand the mechanics of their rifle and want a consistent, repeatable trigger pull under stress.

Overview

The FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 is a purpose-built component from Rare Breed. It is designed to fit HK MR223 and MR556 lower receivers without permanent modification. The three-position selector offers safe, semi-automatic, and forced-reset modes. In the forced-reset position, the trigger resets forward as the bolt cycles, allowing the shooter to manage the timing of each shot. The flat trigger shoe provides a consistent finger placement, reducing the chance of pull variation during rapid strings. This trigger system is machined from billet steel and finished to withstand the high round counts common with HK rifles.

Features & Specs

• Platform-Specific Design: Engineered exclusively for the HK MR223 and MR556 lower receivers. No adapters or modifications needed for proper fitment and function. The trigger housing geometry matches the HK pocket dimensions precisely.
• Three-Position Selector: Positions include safe, semi-automatic, and forced-reset. The forced-reset mode uses the bolt carrier’s forward motion to push the trigger shoe back into position, enabling a controlled, high-speed cycle that requires deliberate finger management from the shooter.
• Flat Trigger Shoe: A smooth, flat face with a slight texture provides a consistent surface for your trigger finger. This reduces lateral movement and helps maintain a straight rearward pull, especially when firing from unconventional positions or with gloved hands.

• Single-Stage Pull: The trigger breaks at a clean, single-stage weight with minimal take-up. There is no creep or stacking, which allows you to focus on the shot rather than fighting through a long pull. The reset is tactile and audible.
• Materials & Finish: Constructed from heat-treated billet steel with a corrosion-resistant coating. The internal components are case-hardened to reduce wear. This trigger is built for the round count you would expect from an HK rifle.
• Drop-In Installation: Uses factory-style pins and requires no trigger job or gunsmith fitting. However, installation should be performed by someone familiar with AR-platform trigger swaps, as proper pin alignment and selector engagement are critical for safety.

Who It Is For

This trigger is for the HK MR223 and MR556 owner who wants a single-stage, flat-faced trigger with forced-reset capability. It suits shooters who train in controlled pairs, run drills that require fast follow-up shots, or compete in divisions where trigger manipulation is a factor. If you are comfortable with the mechanics of a forced-reset system and understand that it demands deliberate trigger discipline, this is a solid upgrade. It is not intended for those who want a traditional two-stage match trigger or who are unfamiliar with how forced-reset triggers function in a semi-automatic platform.

Shipping & FFL

This FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 is a firearm component and does not require transfer through a Federal Firearms License (FFL) for shipment. It can be shipped directly to your door. However, you are responsible for ensuring compliance with all local, state, and federal laws regarding the ownership and installation of aftermarket trigger systems. Some jurisdictions restrict or prohibit forced-reset triggers or three-position selectors. Check your local laws before ordering. Rare Breed and our retailer assume no liability for improper installation or use. If you have questions about legality in your area, consult an attorney or your local firearms authority before purchase.