About this product

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

Rare Breed continues to push the boundaries of trigger engineering with the FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger, a precision-machined drop-in assembly engineered exclusively for the HK MP5, MP5K, SP5, and SP5K platforms. Designed for shooters who demand rapid, repeatable shot cycles without compromising the tactile feedback of a two-stage pull, this trigger system integrates Rare Breed’s patented forced-reset technology into the iconic roller-delayed blowback system. The FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K represents a significant advancement in semi-automatic trigger performance, offering three distinct selector positions: safe, semi-automatic, and forced-reset mode. Each component is CNC-machined from billet steel and hard-coat anodized to military-grade specifications, ensuring dimensional consistency and long-term durability under sustained firing schedules.

Overview

The FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K is a direct replacement for standard SEF (Sicher, Einzelfeuer, Feuerstoss) trigger packs, maintaining factory geometry while introducing an entirely new operating mechanism. Unlike conventional two-stage triggers, the forced-reset system mechanically resets the trigger forward immediately after each shot, reducing lock time and enabling a significantly faster cyclic rate. The two-stage design provides a distinct take-up wall at approximately 2.5 pounds of pull weight, followed by a crisp second-stage break at 4.5 pounds, with the forced-reset function engaging only after the bolt carrier completes its rearward travel. This trigger is not a conversion device; it operates exclusively in semi-automatic mode and complies with all applicable federal regulations as a drop-in component.

Features & Specs

• Manufacturer: Rare Breed; Category: Triggers; Platform compatibility: HK MP5, MP5K, SP5, SP5K (all SEF-pattern lower receivers).
• Three-position selector: Safe (S), Semi-Automatic (E), Forced-Reset (F) with positive detent engagement and audible click at each position.
• Two-stage pull: First stage 2.5 lb (+/- 0.3 lb) take-up; second stage 4.5 lb (+/- 0.3 lb) break; forced-reset return force approximately 1.5 lb.
• Construction: Billet 4140 steel hammer, sear, and trigger; hard-coat anodized black; all internal springs are stainless steel.
• Drop-in installation: No permanent modification to receiver required; includes hardened steel hammer strut, captive trigger pin, and sear spring.
• Bolt travel clearance: Machined to accommodate HK roller-delayed bolt carrier without binding or premature reset engagement.

Who It’s For

The FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K is intended for experienced shooters and competitive marksmen who have a thorough understanding of forced-reset trigger mechanics and the associated safety protocols. This trigger is suitable for range use, tactical training drills, and competition where rapid target transitions and split-times are critical. It is not recommended for novice shooters or for defensive applications requiring a standard single-stage pull. Users should verify compatibility with their specific HK model variant and magazine type before installation. Rare Breed recommends installation by a certified armorer to ensure proper sear engagement and function testing in forced-reset mode.

Shipping & FFL

This product ships directly to your residential or business address. No Federal Firearms License (FFL) transfer is required for this component as it is classified as a firearm parts kit and not a regulated firearm receiver. However, local, state, and municipal laws regarding trigger modifications vary; it is the purchaser’s sole responsibility to verify compliance with all applicable regulations prior to ordering. Rare Breed and this retailer assume no liability for misuse, improper installation, or legal non-compliance. By purchasing this product, you confirm that you are legally eligible to own firearm components and that you will use the FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K in accordance with all federal, state, and local laws.