4UANTUM GHK / VFC AR15 MAGNUS PRO TDC Hop-Up Chamber - Black

4UAD MAGNUS PRO – professional TDC hop-up chamber for GHK / VFC AR15

Looking for the most accurate and most stable hop-up chamber for your GHK or VFC AR15 GBB rifle? Want to shoot farther with higher precision? Need to hit targets consistently at any distance while using heavier BBs? The 4UAD MAGNUS PRO is made exactly for that. This hop-up chamber represents the absolute peak of modern TDC designs. It is CNC machined from a solid block of 6061 aircraft-grade aluminum and uses a true TDC (Top Dead Center) mechanism, meaning the pressure on the bucking is applied straight from above and always evenly. Thanks to its patented self-centering tri-lug barrel lock, the inner barrel stays perfectly centered and fixed without any play. The design also includes a CNC bucking collar that keeps the bucking aligned and provides stable muzzle velocity. Adjusting the hop-up is extremely simple — the adjustment wheel is accessible through the ejection port, so you can fine-tune the setting without disassembling the rifle (using a 1.5 mm hex key or a pointed tool). The chamber is fully compatible with both GHK and VFC platforms (M4/AR15/HK416); for VFC systems, a dedicated spacer is included for perfect fitment. For anyone who demands consistent performance, perfectly straight flight paths, and long-term reliability, the MAGNUS PRO is the ultimate upgrade. Works best with the 4UANTUM Friction GBB bucking (not included).

Installation demo

Key Features

• Vertical TDC system:
  Perfectly even pressure on the bucking with no lateral shift.
  
  
• Self-centering tri-lug lock:
  Patented barrel retention eliminates wobble and guarantees stable accuracy.
  
  
• Easy adjustment:
  Quick hop-up tuning directly through the ejection port — no disassembly needed.
  
  
• Wide compatibility:
  Fits GHK M4 V3, GHK HK416A5, VFC M4 V2/V3, and multiple AR15 GBB platforms.
  
  
• CNC construction:
  Made from 6061 aircraft aluminum for maximum strength and precision.
  
  
• Consistent performance:
  CNC bucking collar ensures perfect alignment and stable muzzle velocity.
  
  
• Two metal pressure nubs:
  Includes two different nubs for fine-tuning hop-up characteristics.

Pair of pressure segments

Technical Specifications

• Material: CNC-machined 6061 aluminum
• Pressure Type: TDC (Top Dead Center)
• Centering Mechanism: Tri-lug lock (self-centering barrel mount)
• Hop-up Adjustment: Via adjustment wheel accessible from the ejection port
• Compatibility – GHK: M4 V3 / HK416A5 (no spacer required)
• Compatibility – VFC: M4 V2/V3 / T91 / BCM MCMR / MK18 / SR-16E3 (with spacer)
• Not Compatible: VFC HK416 Gen2/Gen3, L403A1 EVO GBB, GHK M4 V2
• Manufacturer: 4UAD (Taiwan)
• Color: Black (anodized aluminum)
• Weight: approx. 45 g

Package Contents

• MAGNUS PRO TDC hop-up chamber for GHK / VFC AR15
• CNC hop-up bucking sleeve
• Spacer insert for VFC platforms
• 2 hop-up nubs
• Mounting accessories

Complete package contents