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 from Rare Breed is built for shooters who want a distinct, hands-on trigger experience in their HK-pattern rifle. This isn’t a gimmick—it’s a mechanical trigger system that uses the rifle’s own recoil to reset the trigger shoe, allowing for faster follow-up shots without modifying the lower receiver’s internal geometry. It fits the MR223 and MR556 platforms natively, and the flat shoe gives you a consistent finger placement for repeatable pulls. If you’ve been looking for a trigger that changes how you interact with the gun, this is it.

Overview

The FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & MR556 is a drop-in design that replaces your stock trigger group. It offers three selectable positions: safe, semi-automatic, and forced reset mode. In forced reset mode, the trigger must be fully released after each shot to reset; the bolt carrier’s forward travel pushes the trigger shoe forward, reducing the perceived reset travel. The flat trigger shoe provides a broad, stable surface that works well with gloved hands and minimizes lateral movement during rapid strings. Rare Breed engineered this specifically for the HK MR223 and MR556, so you get a precise fit without filing or fitting. The trigger is machined from billet steel with a nitride finish for corrosion resistance and a crisp single-stage break at approximately 4.5 pounds.

Features & Specs

• Three-position selector: Safe, semi-automatic, and forced reset mode. The forced reset function returns the trigger forward with each bolt cycle, requiring a deliberate finger release before the next shot. This mechanical cycling gives you control over your cadence without any electronic components.
• Flat trigger shoe: The flat face reduces the distance from the bore axis to the trigger contact point, which can help mitigate muzzle rise during fast strings. The textured face prevents your finger from slipping, even in wet conditions.
• Drop-in installation: No gunsmithing required. The FRT-MR3 uses your existing hammer and trigger pins. Standard AR-15 hammer and trigger pins work, though some users prefer anti-walk pins for extra retention. The unit includes a proprietary disconnector and sear designed for the HK platform’s bolt carrier profile.

• Material: Machined billet steel with a melonite/nitride finish. The internal surfaces are polished to reduce friction and ensure consistent reset timing across different ammunition types.
• Weight: Approximately 2.8 ounces. The flat shoe adds a slight weight increase over a curved shoe but provides a more neutral finger angle.
• Compatibility: Specifically tested for HK MR223 and HK MR556. Will not fit standard AR-15 lowers without modification due to the different bolt carrier tail dimensions.

• Pull weight: 4.5 to 5.0 pounds, single-stage. There is no take-up or creep in forced reset mode; the break is clean with a distinct wall.
• Reset: Forced reset in the third position. The trigger must travel fully forward before the sear re-engages. This prevents bump-firing and ensures each shot is a deliberate trigger release.
• Safety: The safe position blocks the trigger bow and sear movement. The selector stops are positive and audible.

Who It’s For

This trigger is for the HK MR223 and MR556 owner who wants to experience a mechanical forced reset system without permanent modifications to their rifle. It’s designed for shooters who train with controlled pairs, transition drills, or competition stages where split times matter but full-auto isn’t an option. The flat shoe appeals to those who prefer a more vertical finger position, particularly if you have longer fingers or shoot with a high grip. If you’ve used other forced reset triggers in the past and want a dedicated HK-platform unit with a flat trigger face, this is the specific product you’ve been waiting for. The FRT-MR3 (Flat) Single-Stage (3-Position) Forced Reset Trigger for the HK MR223 & HK MR556 is not a novelty—it’s a training tool that reinforces proper trigger discipline because you must fully release the trigger between shots.

Shipping & FFL

This trigger is classified as a firearm component and does not require an FFL transfer for shipping. It can be shipped directly to your residential or business address. However, you must comply with all applicable federal, state, and local laws regarding trigger ownership and installation. Some states and municipalities have restrictions on forced reset triggers or binary-style trigger systems. It is your responsibility to verify that this product is legal to own and install in your jurisdiction before placing an order. Rare Breed and our retail location assume no liability for non-compliance with local regulations. By purchasing this item, you confirm that you are not prohibited from owning firearm parts and that you will install the trigger in compliance with all laws. We ship via UPS Ground or FedEx with adult signature required. Expedited shipping is available at checkout.