4UANTUM Hop-Up Bucking Friction Pro - GBB Bucking & Nub

Precision Engineering by 4UAD

Known for their rigorous, scientific approach to airsoft performance, the 4UAD SmartAirsoft team has channelled their immense analytical expertise into the 4UANTUM Friction Pro GBB Bucking. Gas blowback rifles and VSR-spec snipers are notoriously demanding when it comes to hop-up consistency, often suffering from erratic shot placement due to uneven hop pressure or poor air seals. This bucking has been designed from the ground up to solve those exact issues, giving you tournament-grade performance in a simple, reliable drop-in package.

Flawless BB Centring

The magic of the Friction Pro lies inside the rubber. It utilises a carefully sculpted internal contact patch that acts as a stabilising cradle for the BB. When your loading nozzle pushes the BB into the chamber, this unique contour automatically guides it to the dead centre of the barrel. By ensuring the projectile is perfectly aligned before the backspin is applied, horizontal deviation is practically eliminated. Your shots will fly dead straight, dramatically tightening your groupings at medium to long distances.

Perfect for Snipers and GBBRs

If you are running a high-end gas blowback assault rifle or a tuned bolt-action sniper, you are likely using heavier ammunition to punch through woodland brush and resist wind deflection. The Friction Pro includes a custom-matched tensioner nub that seats perfectly against the bucking. Together, they generate massive, uniform friction. This allows you to effortlessly lift heavier weights—such as 0.30g, 0.36g, or even 0.40g+ BBs—providing a beautifully flat flight path without needing to over-apply hop and unnecessarily bleed off muzzle velocity.

Seamless GBB & VSR-10 Compatibility

Built to the widely accepted industry standard, this bucking is a direct drop-in fit for Tokyo Marui spec Gas Blowback pistols (including WE, KJW, and TM), gas blowback rifles (GBBRs), and VSR-10 bolt-action sniper rifles. It is manufactured from a highly durable, tear-resistant silicone compound that creates an exceptional, airtight seal around your nozzle. Furthermore, this premium material retains its elasticity even in freezing conditions, helping to combat the dreaded cool-down effect common in gas platforms during the harsh British winter.

Key Features at a Glance

• 4UAD Developed: Engineered through meticulous, data-driven testing by the experts at 4UAD SmartAirsoft.

• Auto-Centring Design: Specialised contact patch guides the BB perfectly down the centre of the barrel for straight-line accuracy.

• Included Custom Nub: Comes with a matched tensioner nub for optimal, even pressure distribution.

• VSR/GBB Spec: Drop-in compatible with TM-spec gas pistols, gas blowback rifles, and VSR-10 snipers.

• Heavy BB Optimised: Delivers immense lifting power, ideal for DMR and heavy sniper-weight ammunition.

• Cold-Weather Resistant: Premium silicone compound maintains flexibility and its perfect air seal even in freezing temperatures.

• Maximum Consistency: Eliminates side-to-side flyers for predictable, laser-like precision on the skirmish field.