Description

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

The FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K represents a significant advancement in aftermarket trigger systems for the roller-delayed blowback platform. Engineered by Rare Breed, this trigger unit replaces the factory SEF (Sicher, Einzelfeuer, Feuerstoss) pack, providing a forced-reset mechanism that operates through a distinct three-position selector. Designed for end users who require a repeatable, high-speed reset cycle, the FRT-RD3™ maintains compliance with applicable federal regulations while offering a mechanically unique shooting experience.

Overview

The FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K is a drop-in trigger pack built to the exact dimensional standards of the original HK SEF housing. It utilizes a forced-reset geometry that returns the trigger forward under spring tension immediately after each shot, allowing the shooter to pre-stage the trigger for a subsequent discharge. The three-position selector replicates the classic HK layout: safe, semi-automatic, and a third position that enables the forced-reset function. This trigger is manufactured from hardened steel and aerospace-grade aluminum components, ensuring longevity under sustained use. It is compatible with both full-size MP5 variants and the compact MP5K, as well as the civilian SP5 and SP5K models.

Features & Specs

• Three-position selector (safe, semi-automatic, forced-reset) with positive detent engagement and audible click indexing at each stop.
• Two-stage trigger pull: a defined take-up stage followed by a crisp, consistent break at approximately 4.5 pounds (tested at factory).
• Drop-in installation into standard SEF trigger housings; no permanent modifications to the host firearm required.

The FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K features a billet-machined hammer with a hardened striking face, a nickel-Teflon coated sear for reduced friction, and a stainless steel trigger bow. All internal springs are made from chrome-silicon wire for consistent cycling across temperature ranges. The pack is assembled with Mil-Spec fasteners and includes a captive hammer pin. Rare Breed certifies each unit to function within a cyclic rate range of 600 to 900 rounds per minute when the forced-reset mode is selected, dependent on ammunition and buffer configuration.

Who It’s For

This trigger is intended for experienced shooters and competitive platform enthusiasts who own an HK MP5, MP5K, SP5, or SP5K and seek a mechanically repeatable reset system without altering the firearm’s receiver. It is suited for those familiar with forced-reset trigger mechanics and who understand the manual of arms required to operate the three-position selector correctly. The FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K is not recommended for novice users or for use in fully automatic host firearms. It is designed exclusively for semi-automatic and forced-reset cycling in compliant configurations. Users should verify state and local laws prior to purchase, as certain jurisdictions restrict the ownership or use of forced-reset trigger systems.

Shipping & FFL

This FRT-RD3™ (SEF) Two-Stage (3-Position) Forced Reset Trigger for the HK MP5, MP5K, SP5 & SP5K is classified as a firearm component and does not require transfer through a Federal Firearms License (FFL) for shipment to most U.S. addresses. However, some states and municipalities impose additional regulations on trigger assemblies, particularly those with forced-reset functionality. It is the purchaser’s sole responsibility to ensure compliance with all applicable federal, state, and local laws. Rare Breed and this retailer disclaim all liability for misuse or unlawful possession. Standard shipping rates apply; allow 5–10 business days for delivery. No returns or exchanges on installed trigger packs. By purchasing this product, you confirm that you are at least 18 years of age and legally eligible to own firearm components in your jurisdiction.