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

If you run a roller-delayed HK platform, you know the trigger is where the personality of the gun lives. The FRT-RD3 (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 and SP5K brings a new level of control to that classic action. Built by Rare Breed, this drop-in unit gives you a crisp two-stage pull with a forced-reset function that puts the next shot under your thumb faster than a standard trigger lets you. It fits standard SEF housings and works with both full-size and K models, so whether you are running a SP5 at the range or a MP5K in a class, this trigger adapts to your setup.

Overview

The FRT-RD3 is a three-position, two-stage trigger that uses a forced-reset mechanism. In the first position, you get a standard semi-auto pull with a clean break. In the second position, the trigger resets forward automatically after each shot, letting you ride the reset without lifting your finger. The third position is a safe, manual-safety lockout. This design does not change the legal function of your firearm; it simply gives you a faster, more predictable reset cycle. Rare Breed engineered it specifically for HK roller-lock guns, so you get drop-in fitment without modifying your lower or bolt carrier group.

Features and Specs

• Three-position selector: safe, semi-auto, and forced-reset semi-auto (FRT mode)
• Two-stage trigger pull with a defined wall and a crisp, predictable break
• Drop-in design for standard SEF (Navy-style) trigger housings on MP5, MP5K, SP5, and SP5K
• Hardened steel internal components with a corrosion-resistant finish
• Manufacturer tested for function across a range of ammunition types and bullet weights

This trigger does not require any permanent modifications to your firearm. It installs into your existing SEF pack with standard pins and uses the factory hammer spring. The forced-reset action works by using a cam that re-engages the sear as the bolt cycles, so the trigger returns forward immediately after the shot breaks. You still pull the trigger for each round; the mechanism simply speeds up the reset portion of the cycle. Rare Breed designed the FRT-RD3 to be reliable with 9mm ammunition from 115-grain to 147-grain loads, including +P and subsonic.

Who It Is For

This trigger is for the HK owner who wants to shoot faster without losing accuracy. If you run a SP5 in competition, the forced-reset mode lets you keep your finger on the trigger and fire quickly while maintaining a clean break on each shot. For MP5K owners who shoot defensive drills or sub-gun matches, the FRT-RD3 gives you a consistent pull that resets predictably under recoil. It also suits collectors and enthusiasts who appreciate the engineering behind a two-stage forced-reset system and want to experience it on a roller-lock platform. If you prefer a standard single-stage trigger, this may not be your choice, but if you want a trigger that rewards deliberate, fast shooting, it is worth trying.

Shipping and FFL

This trigger ships directly to your residential or business address. No FFL transfer is required because the FRT-RD3 is a trigger assembly, not a firearm receiver or a regulated part under federal law. However, you must comply with all state and local laws regarding trigger modifications and firearm parts. Some states or municipalities may have restrictions on forced-reset triggers or trigger mechanisms that alter the firing cycle. It is your responsibility to verify that this product is legal to own and install in your jurisdiction before placing an order. We do not accept returns on trigger components that have been installed or used. If you have any questions about compatibility with your specific HK model, contact our support team before purchase.