About the Rare Breed FRT-RD3 Ambi Two-Stage

FRT-RD3 (Ambi) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K

The FRT-RD3 (Ambi) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K represents a precision-engineered upgrade for roller-delayed blowback platforms. Manufactured by Rare Breed, this ambidextrous forced reset trigger delivers a distinct two-stage pull with three selectable positions, allowing the operator to manage shot timing with mechanical consistency. Designed specifically for the HK MP5, MP5K, SP5, and SP5K, this trigger maintains the platform's reliability while providing a tactile reset that enhances control during rapid strings of fire.

Overview

The FRT-RD3 (Ambi) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K redefines the trigger interface on one of the most iconic sub-machine gun platforms in service. Rare Breed has engineered a drop-in assembly that replaces the factory trigger pack without permanent modification to the firearm. The three-position selector allows the shooter to choose between safe, standard semi-automatic, and the forced-reset mode. In forced-reset mode, the trigger mechanism mechanically resets the trigger forward after each shot, requiring the shooter to intentionally release and re-depress the trigger for each subsequent round. This mechanical action provides a consistent, repeatable trigger pull that reduces the variables introduced by human timing.

Features & Specs

• Ambi selector lever accommodates both right-handed and left-handed shooters without adapter plates or modification.
• Two-stage trigger pull: a short take-up stage followed by a crisp, defined wall before the break point.
• Three-position selector: safe (rear), semi-automatic (middle), forced-reset (forward) with positive detents at each position.

The FRT-RD3 (Ambi) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K uses a hammer-forged steel sear and hardened tool steel engagement surfaces. The trigger housing is CNC-machined from 7075-T6 aluminum with a Type III hard coat anodized finish. Each unit is hand-assembled and function-tested at the Rare Breed facility before shipment. The forced-reset mechanism cycles reliably within the roller-delayed action, maintaining consistent trigger weight across all three positions.

• Drop-in fit for HK MP5, MP5K, SP5, and SP5K platforms - no gunsmithing required.
• Trigger pull weight: 5.5 to 6.5 pounds across all positions, measured at the factory.
• Overall length of trigger cassette matches factory specifications for direct installation.

Who It's For

This trigger is built for the experienced HK platform owner who demands mechanical precision over variable human input. Competitive shooters training in speed and accuracy drills will benefit from the forced-reset mode's consistent timing. Law enforcement and security professionals using MP5-platform firearms will find the ambidextrous selector advantageous in dynamic environments. Collectors and enthusiasts who maintain multiple HK variants appreciate the single trigger unit that works across MP5, MP5K, SP5, and SP5K models. The FRT-RD3 (Ambi) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K is not a novelty item; it is a functional upgrade for shooters who understand the mechanics of their firearm and want to reduce shot-to-shot variability.

• Applicable for range training, competition, and defensive proficiency development.
• Suitable for shooters who prefer a two-stage break over a single-stage or mil-spec trigger.
• Compatible with standard HK lower receiver groups requiring no permanent alteration.

Shipping, returns and FFL transfer

• Parts and accessories ship to your door where state and local law allow.
• Shipping is $29.99 per order, free on orders over $999. Orders usually leave within 1–3 business days after payment clears.
• Unused items in original packaging can be returned within 30 days of delivery.

Full terms: shipping and FFL transfers · returns and refunds · FAQ · contact us.

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