FRT-MR3™ (MIL)

The FRT-MR3™ (MIL) is a single-stage (3-position) forced reset trigger from Rare Breed Triggers, engineered for the HK MR223 & MR556. This drop-in, duty-grade Safe/Semi/FRT® trigger is 100% manufactured and assembled in the USA for fast, controlled follow-up shots with simple, no-gunsmithing installation.

Take your HK MR223 and HK MR556 to the next level with the official Rare Breed Triggers FRT-MR3™ (MIL). This drop-in, duty-grade 3-position Forced Reset Trigger (Safe/Semi/FRT®) is 100% manufactured and assembled in the USA. The FRT-MR3™ (MIL) replicates the classic style of a Mil-Spec style trigger, hammer and trigger pins, and selector, but takes it to the next level with a 3-position forced reset trigger, A1 and A4 safety selector bodies, and Mil-Spec Hammer and Trigger pins for a secure, hassle-free installation.

Performance on the Range

Enhance your shooting experience with the FRT-MR3™ (MIL) Forced Reset Trigger. Designed to accelerate follow-up shots while remaining within legal parameters, the innovative Forced Reset system resets the trigger after each shot, enabling faster, more consistent firing. Each trigger pull fires one round, ensuring full legal compliance while delivering improved speed and performance. Perfect for competitive shooting, tactical training, or maximizing your HK MR223 and HK MR556’s potential.

Innovative Design and Features

3-Position Functionality: The FRT-MR3™ (MIL) features Safe, Semi, and Forced Reset modes, controlled via a 3-position Mil-Spec safety selector. Whether you’re focused on precision shooting or rapid-fire drills, this system adapts to your needs.

Effortless Installation: Designed for easy installation on HK MR223 and MR556 lowers, the FRT-MR3™ (MIL) includes Mil-Spec hammer and trigger pins, providing secure attachment and preventing unwanted movement during extended use. The A1 (0/90/180) and A4 (0/45/90) safety bodies seamlessly integrate into HK MR223 and MR556 lower receivers while reusing the stock levers.

Durable Construction for Long-Lasting Performance

Crafted from high-quality materials, including 7075 anodized aluminum and heat-treated 4140 and S7 steel, the FRT-MR3™ (MIL) is built to endure heavy use. This robust construction ensures reliability and longevity, allowing you to push your HK to its limits with confidence.

Compatibility with the HK MR223 and HK MR556

The FRT-MR3™ (MIL) is specifically engineered to operate with the factory semi-automatic bolt carrier group (BCG) used in the HK MR223 and HK MR556 platforms. For that reason, the FRT-MR3™ (MIL) is compatible with the HK MR223 and MR556 uppers when used with the original, factory-supplied semi-auto BCG. For optimal performance and reliability, we recommend retaining the factory buffer and recoil spring. Please note: The FRT-MR3™ (MIL) is not compatible with HK416 or BRN4 full-auto bolt carrier groups.

Unmatched Speed and Control

The FRT-MR3™ (MIL) is ideal for shooters seeking speed and precision. By mechanically resetting the trigger after each shot, then locking the trigger from being pulled until the BCG returns to battery, this system allows for faster follow-up shots without needing advanced techniques. The forced reset mechanism ensures the trigger returns to the non-firing position after each round, requiring the shooter to pull the trigger again, offering full control over each shot.

Why Choose the FRT-MR3™ (MIL) Forced Reset Trigger?

If you’re looking to boost your HK MR223 and HK MR556’s performance while maintaining the traditional look of a Mil-Spec trigger and safety selector, the FRT-MR3™ (MIL) Forced Reset Trigger is the ultimate upgrade. With its rapid-fire capability, secure anti-rotation design, and seamless compatibility with the HK MR223 and HK MR556 platforms, this trigger provides a superior shooting experience for competition, tactical use, or range drills. Unlock the full potential of your HK MR223 and HK MR556 with the FRT-MR3™ (MIL).

Manufactured and Assembled in the USA

What’s in the box

• 1 x FRT-MR3 (MIL) Trigger
• 2 x Mil-Spec Hammer and Trigger Pins
• 1 x A1 Selector Drum
• 1 x A4 Selector Drum
• 2 x Selector Lever Roll Pins

FAQ

Does the FRT-MR3™ (MIL) fire more than one round per trigger pull?
No. Rare Breed Triggers states each pull of the trigger fires one round; the forced reset system mechanically resets the trigger after each shot and locks it until the bolt carrier returns to battery.

Is the FRT-MR3™ (MIL) a drop-in trigger?
Yes — it is designed as a drop-in trigger for the HK MR223 & MR556 with no gunsmithing, fitting, or machining required.

Single-stage or two-stage?
The FRT-MR3™ (MIL) is a single-stage trigger in semi-automatic mode (see the pull-weight details above).

Related forced reset triggers

• FRT-MR3™
• FRT-MR3™ (FLAT)
• all forced reset triggers at Next Level Triggers

Patent Notice: This product is covered by one or more U.S. Patents, including U.S. Patent Nos. 10,514,223; 11,724,003; 12,036,336; 12,274,807; and 12,636,403. Additional patents may be pending. Unauthorized manufacture, use, sale, or importation of this product or its covered features may constitute patent infringement. As always, Rare Breed Triggers encourages the safe and responsible use of our products.

Legal notice: Forced reset triggers are regulated differently across jurisdictions and their status can change. Confirm current federal, state, and local laws before purchasing. Must be 21+ . Rare Breed Triggers encourages the safe and responsible use of its products.