Perun G28 / HK 417 (VFC) Trigger Unit

Perun for G28 / HK417 by VFC – Drop-in ETU with Integrated Adjustable Clicker

Transform your VFC G28 or HK417 airsoft replica into a high-performance DMR or battle rifle with the Perun for G28 / HK417 MOSFET. This dedicated drop-in electronic trigger unit (ETU) replaces the entire stock trigger block with a custom housing that includes an integrated adjustable Clicker and advanced Perun electronics. It delivers crisp magnetic trigger detection, reliable optical sensors, and a full suite of programmable features — making it the ultimate upgrade for semi-only or versatile VFC G28/HK417 platforms.

Custom Housing with Integrated Adjustable Clicker

The Perun G28 / HK417 ETU features a purpose-built housing that directly replaces the stock trigger block. Inside, you get a built-in adjustable Clicker that simulates a real firearm trigger break. Fine-tune pre-travel, over-travel, and break force (even down to zero for ultra-short, competition-style pulls) using adjustment screws. This gives you complete control over trigger feel without any permanent modifications to the trigger or gearbox.

Advanced Hybrid Sensor Technology

• Magnetic trigger detection (Hall-effect sensors) — Provides an incredibly crisp, consistent, and responsive trigger pull with zero mechanical wear.
• Optical sensors for selector position and sector gear detection — Ensures precise, reliable operation even in high-stress builds.

The system includes a custom cut-off lever for dependable semi-auto function and supports DSG mode optimised for dual-sector gears. External magnetic field detection adds an extra layer of safety to prevent accidental shots.

Powerful, Programmable Features for DMR Performance

• Active Brake — Instantly stops the motor after each shot to prevent overspin, double-feeding, and unwanted spring compression. Adjustable strength for perfect control.
• Pre-cocking — Keeps the piston pre-tensioned for near-zero trigger lag and lightning-fast follow-up shots — essential for precise DMR shooting. Safe spring release: pull and hold the trigger for 2 seconds (fires a second shot without pre-cocking and fully braked).
• Fully Programmable Firing Modes — Independently set modes for short or long trigger pulls on each selector position: SEMI ONLY, BINARY (fire on pull and release), SEMI-AUTO, SEMI-BURST, BURST-AUTO, and more.
• 2-Stage Trigger — Light pull for one mode, deeper pull for another.
• DMR Mode — Enforces mandatory intervals between semi shots (0.25s to 3s) for field compliance or added realism (mimics recoil effects of a real 7.62mm rifle).
• Rate of Fire Reduction — Lower ROF in auto or burst modes while keeping the first shot crisp — great for ammo conservation or realistic feel.
• DSG Compatibility — Special sector gear detection mode for dual-sector gear setups.

All programming is performed quickly on the field using simple fire selector + trigger sequences, with clear feedback from a multicolour LED and audio beeps. No apps or computers needed. Factory defaults are well-balanced, and a full reset is easy.

Robust Protections and Diagnostics

• Electronic resettable fuse — Protects against short circuits and gearbox jams.
• Low battery voltage alarm — Audible alerts for Li-Po and Li-Ion packs (can be toggled on/off).
• Advanced diagnostic system — Constantly monitors the replica and alerts you to issues like jams, overheating, sensor faults, or mechanical problems via sound and LED signals.

The unit supports brushed and brushless (BLDC) motors, any gear ratio (including short-stroked, helical, or DSG), and works flawlessly with stock or upgraded VFC gearboxes (including Retro Arms CNC shells). It handles any spring rating in extreme high-power builds.

Easy Drop-in Installation for VFC G28 & HK417

This true drop-in design makes installation straightforward for users with basic technical knowledge. The custom housing and pre-configured board fit VFC G28 and HK417 replicas perfectly, retaining stock trigger compatibility while adding modern electronic precision. A T-Plug (Deans) connector is pre-soldered.

Note: Always follow the official manual. Improper installation may damage the unit.

What’s Included

• Perun for G28 / HK417 kit: Custom housing with integrated Clicker and Perun electronic board
• Custom cut-off lever
• All necessary magnets and mounting elements
• Detailed installation and programming instructions

Technical Specifications

• Voltage range: 7–17 V (Li-Po / Li-Ion recommended; high C-rating and capacity advised)
• Sensors: Magnetic (trigger) + Optical (selector & sector gear)
• Trigger: Adjustable pre-travel, over-travel, and break force via integrated Clicker; 8 sensitivity levels for 1st and 2nd stage
• Firing modes: Fully independent and programmable per selector position
• Active Brake & Pre-cocking: Yes, with adjustable settings and safe release
• Protections: Electronic resettable fuse, low-voltage alarm, diagnostic system, external magnetic field detection
• Stand-by current: Very low (approx. 1 mA in SAFE)
• Compatibility: VFC G28 and HK417 replicas (stock or Retro Arms CNC gearbox shells); any gears including DSG
• Conformal coating: For humidity and water resistance

Why Choose the Perun for G28 / HK417 MOSFET?

As the first and only dedicated ETU specifically engineered for the VFC G28 and HK417 platforms, this unit addresses the platform’s unique trigger block geometry while adding premium features like an adjustable Clicker, magnetic trigger detection, pre-cocking, binary trigger, and DMR mode. It turns your semi-only battle rifle into a reliable, responsive, and highly customisable DMR without the hassle of complex wiring or gearbox overhauls. Perfect for serious airsoft snipers, DMR enthusiasts, or players wanting realistic 7.62mm-style performance.

Elevate your VFC G28 or HK417 with the Perun for G28 / HK417 by VFC — the smartest, most feature-packed drop-in ETU with integrated Clicker for precision semi-auto dominance.

Perun G28 HK417 MOSFET | Drop-in ETU for VFC G28 HK417 | Integrated Adjustable Clicker | Magnetic Trigger Detection | Optical Sensors | Active Brake | Pre-cocking | Programmable Firing Modes | Binary Trigger | DMR Mode | DSG Compatible | Adjustable Trigger Break Force