Description

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

Rare Breed continues to push the boundaries of trigger engineering with the FRT-RD3, now available in the Single-Edge Fire (SEF) configuration for the HK roller-delayed platform. This is a two-stage, three-position forced reset trigger specifically designed for the HK MP5, MP5K, SP5, and SP5K. It offers a mechanical cycling rate that is entirely dependent on the shooter’s trigger finger, providing a positive reset feel that is distinct from traditional binary or standard semi-automatic triggers. The FRT-RD3 (SEF) operates on a true forced reset principle, where the trigger must fully reset forward after each shot before it can be pulled again, creating a rapid-fire capability that is both controlled and repeatable.

Overview

The FRT-RD3 (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 and SP5K is engineered for shooters who demand maximum performance from their roller-delayed firearm. This trigger replaces the factory trigger pack with a drop-in unit that requires no permanent modifications to the host weapon. The three-position selector allows the shooter to choose between Safe, Semi-Automatic, and the Forced Reset mode. In the forced reset position, the trigger mechanically forces the sear to disengage after each cycle, requiring the shooter to release the trigger fully before the next shot can occur. This design eliminates the possibility of hammer follow and ensures consistent lock time with every round fired. The two-stage pull weight is factory-set to provide a distinct wall before the forced reset function engages, giving the shooter tactile feedback that is critical for maintaining accuracy at elevated firing rates.

Features and Specs

This FRT-RD3 (SEF) trigger is constructed from heat-treated steel components with a corrosion-resistant finish, ensuring long-term reliability in adverse conditions. The housing is precision-machined to fit the HK MP5, MP5K, SP5, and SP5K lower receiver without any fitting or handwork required. The two-stage design provides a light take-up followed by a crisp second stage break when used in semi-automatic mode. In the forced reset position, the trigger resets forward with an audible and tactile click, allowing the shooter to maintain a consistent cadence.

• Three-position selector: Safe, Semi-Automatic, and Forced Reset (FR) mode
• Two-stage trigger pull: First stage take-up of approximately 2.5 lbs, second stage break at 4.5 lbs (semi-auto mode)
• Drop-in design: No permanent modifications to the HK MP5, MP5K, SP5, or SP5K required; uses factory hammer and trigger pins

The forced reset mechanism is designed to function with standard factory ammunition and does not require specific bullet weights or velocities to cycle reliably. The trigger return spring is engineered to provide consistent reset force across the entire operating temperature range. Each unit is individually function-tested at the factory before shipment.

• Material: Heat-treated 4140 steel hammer and sear, 7075-T6 aluminum housing
• Finish: Mil-spec hardcoat anodized housing, manganese phosphate hammer and sear
• Compatibility: HK MP5, MP5K, SP5, SP5K (will not fit full-size MP5 or SP5 with paddle magazine release without modification)

Who It Is For

The FRT-RD3 (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 and SP5K is intended for experienced shooters who understand the mechanical principles of forced reset triggers and can safely operate a firearm equipped with this technology. It is designed for use at the range, in competitive shooting events that allow forced reset triggers, and for training scenarios where rapid follow-up shots are required. This trigger is not recommended for novice shooters or for use in defensive carry applications due to the unique manipulation required in forced reset mode. The shooter must maintain positive trigger finger control at all times, as the forced reset function requires deliberate trigger manipulation to achieve maximum cyclic rates.

Shipping and FFL

This FRT-RD3 (SEF) trigger is classified as a firearm component and is not a complete firearm, but it is regulated as a firearm part under federal law. It will ship directly to your residential or business address in all states where ownership is legal, unless restricted by state or local laws. You must be 18 years of age or older to purchase this trigger. No Federal Firearms License (FFL) transfer is required for this item, as it is a trigger assembly and not a receiver or complete firearm. However, you are responsible for ensuring that this trigger is legal to own and install in your particular state and municipality. Rare Breed and our company assume no liability for compliance with local laws. All sales are final on this item due to its specialized nature. Please verify your state and local laws regarding forced reset triggers prior to purchase.