Rare Breed Triggers FRT-RD3™ (AMBI) — Forced Reset Trigger for HK MP5 / MP5K / SP5 / SP5K

The Rare Breed Triggers FRT-RD3™ (AMBI) is the world’s only Forced Reset Trigger built specifically for HK MP5, MP5K, SP5 and SP5K roller-delayed firearms. At $620 it’s Rare Breed’s flagship — engineered from scratch for HK’s legendary roller-delayed action, with full ambidextrous safety selector support and everything needed for a complete installation.

Why the FRT-RD3 is the Top of the Rare Breed Lineup

The MP5 and SP5 have a cult following for good reason — they’re among the most reliable and accurate pistol-caliber platforms ever made. The FRT-RD3 takes that platform and adds the mechanical advantage of forced reset technology: dramatically faster follow-up shots while maintaining one-round-per-pull semi-auto operation. No NFA. No machine gun classification. Just faster shooting.

What’s in the Box

• 1x FRT-RD3™ (AMBI) Trigger Assembly
• 3-position ambidextrous safety selectors for HK AMBI pattern
• All necessary hardware for installation
• Installation instructions

Specifications

Pros & Cons

• ✅ Only FRT available for HK MP5/SP5 platform
• ✅ Full AMBI selector — works for left and right-handed shooters
• ✅ Drop-in — no gunsmith, no permanent mods
• ✅ 100% USA made by the original FRT inventors
• ✅ No NFA — semi-auto, one round per pull
• ⚠️ MP5/SP5 platform only — not for AR-15
• ⚠️ Not available to CA, CT, DE, HI, IL, MA, MD, NJ, NY, OR, RI, WA, DC

FAQ

Does it fit the civilian SP5?

Yes — the FRT-RD3 AMBI is compatible with the civilian HK SP5 and SP5K, as well as the MP5 and MP5K.

Is it a machine gun?

No. The FRT-RD3 fires one round per trigger pull. It is semi-automatic by both legal and mechanical definition.

AMBI vs SEF?

The AMBI version ($620) includes ambidextrous safety selectors for HK AMBI-pattern firearms. The SEF version ($615) includes traditional SEF-pattern selectors. Choose based on your firearm’s selector pattern.