VKS | Bullpup Straight-Pull Bolt Action Airsoft Rifle

VKS The return of Silverback’s bullpup expertise

Since 2015, Silverback has developed high-performance spring-powered bolt-action rifles, with the SRS platform becoming a reference for consistency, silence, and mechanical efficiency.

In 2021, the TAC-41 brought a traditional layout focused on accessibility and modularity.

With the VKS, Silverback returns to its bullpup roots. It combines compact modern ergonomics with proven mechanical solutions from the SRS and TAC-41 platforms — including the same cylinder, piston, spring guide, and 41 cc air volume — while adding a TDC hop-up, 63-round double-stack magazine, and tool-less maintenance design.

 

The VKS is equipped with a long CNC picatinny rail, and no iron sights, like on the most recent VKS models. The use of a scope on a Picatinny mount is therefore mandatory.

The rifle is supplied with two side Picatinny rails made from fiberglass reinforced Nylon. These rails can be removed for users who prefer a cleaner and more streamlined appearance, or can be used to mount accessories to the rifle.

 

Proven Mechanical Platform

The VKS uses the same core mechanical architecture as the SRS platform.

Key shared components:

• SRS-compatible cylinder
• SRS-compatible piston
• SRS-compatible spring guide
• SRS-compatible APS 13 mm springs

Cylinder specifications:

• Bore: 23.8 mm
• Stroke: 92 mm
• Usable air volume: 41 cc

This compatibility provides immediate access to the full range of existing Silverback SRS upgrade and spare parts:

• SRS VMP piston
• Advance piston head
• Aluminium/Teflon spring guide

The VKS is equipped with the silent piston head with airbrake.

The longest airbrake is installed out-of-the-box.

Airbrake selection can be optimized depending on:

• Inner barrel length
• BB weight
• Desired performance characteristics

As a general rule, longer barrels and heavier BBs benefit from shorter airbrakes.

Airbrakes can also be used as an additional method to fine tune muzzle energ

 

Highly efficient suppressor system

The VKS suppressor uses a fiberglass construction inspired by the real firearm.

The surface finish is intentionally relatively raw, matching the appearance and texture of the original design. It made from industrial fiberglass/black epoxy tubes, surface state and patterns will be different from one to another.

 

The suppressor is divided into 2 sections:

Back section

The first third of the suppressor provides axial barrel alignment and can be used to stabilize longer inner barrels.

Maximum supported lengths:

• Full Size Suppressor: up to 571 mm, fully supported with barrel spacer
• Half Size Suppressor: up to 467 mm, fully supported with barrel spacer

20 mm barrel spacers are required

Front section

The remaining two thirds use Silverback’s proven baffle foam architecture.

Combined with the extremely large internal volume, the VKS suppressor provides outstanding sound reduction.

For players looking for a more compact configuration, a Half Size Suppressor is available as an option, keeping the same visual identity while reducing overall length by half.

*Depending on the location of your retailer, this item may come without foam inserts due to local laws and regulations, please get in touch with the retailer prior purchase for confirmation.

 

Adjustable and modular hop-up system

The VKS hop-up system uses the SRS form factor with the TDC adjustment philosophy introduced on the TAC-41 platform.

The hop-up chamber keeps the same diameter and length as the SRS hop-up system, while introducing a top-down adjustment system for improved consistency.

The VKS hop-up chamber is currently compatible only with the dedicated VKS outer barrel.

The VKS is supplied with three different hop-up nubs:

• Low nub (+0 µm) – factory installed
• Medium nub (+250 µm)
• High nub (+500 µm)

A taller nub allows additional hop-up effect when required by your setup. Conversely, if your configuration experiences feeding resistance or BB jams, switching to a lower nub can improve reliability.

 

 

Tool-less quick maintenance

Inspired by the real VKS rifle, the airsoft version was designed around a simple and intuitive disassembly process.

The rifle can be largely disassembled without tools by simply removing two pins. This allows the complete bolt assembly to be removed quickly for:

• Cleaning
• Lubrication
• Spring replacement
• Airbrake adjustment
• Internal maintenance

 

 

Trigger Group & adjustable piston sear

The VKS sear system is using the same “open sear” design as this optional part on the SRS. This design allow a smooth piston lock. This piston sear is adjustable.

 

The safety selector is located on the rear left side of the rifle and features two positions: fire and safe.

The piston sear can position can be adjusted, a finer adjustment can significantly reduce trigger pull weight, however excessive adjustment may affect safety and reliability.

Piston sear adjustment tutorial:

Configurable ejection port cover

The VKS ejection port cover can be configured in two different ways:

Dynamic configuration: the ejection port opens when the bolt is operated, reproducing the realistic operation of the firearm.

Fixed configuration: the ejection port remains permanently closed. This configuration reduces exposure of the internal mechanism to dust, dirt, rain, and harsh environmental conditions. While less realistic, it is recommended for players operating their VKS in demanding outdoor environments.

Left-hand conversion

The VKS can easily be converted from right-hand to left-hand operation.

The conversion requires the dedicated left-hand bolt handle: SBA-BTH-80 (sold separately)

 

Easy maintenance 63 BBs capacity magazine

The VKS magazine features a 63 BBs capacity and maintenance friendly architecture.

 

The internal mechanism can be removed almost entirely without screws, making regular maintenance and cleaning quick and easy.

Only the internal magazine shells require screws for complete disassembly.

 

 

 

SRS-compatible outer barrel options

The VKS outer barrel mounting system is almost identical to our SRS line.

 

SRS outer barrels can be installed on the VKS when equipped with a FAST hop-up chamber.

When using a FAST hop-up system, the VKS is supplied with a dedicated cover replacing the external hop-up adjustment wheel, providing a more realistic appearance.

A dedicated FAST hop-up adjustment tool can be downloaded and printed here.

And here it’s a video tutorial on how to use an SRS barrel on your VKS

 

Realistic materials and construction

The VKS was designed with a strong focus on realism and quality, both visually and mechanically.

The rifle combines:

• Fiberglass reinforced Nylon polymer components
• Stamped steel top cover
• Fiberglass suppressor
• CNC machined aluminium internal receiver

The internal receiver follows the SRS philosophy, using a CNC aluminium extrusion design combined with a more minimalist architecture thanks to the stamped steel top cover.

Steel components receive a hot black oxide treatment for protection.

However, like real firearms, steel components require proper care. Regular cleaning and lubrication are recommended to prevent corrosion, especially on:

• Top cover
• Trigger guard
• Suppressor muzzle cap and base
• Safety selector
• Buttplate base
• Bolt handle

Rails

The VKS is equipped with a long CNC picatinny rail, and no iron sights, like on the most recent VKS models. The use of a scope on a Picatinny mount is therefore mandatory.

The rifle is supplied with two side Picatinny rails made from fiberglass reinforced Nylon. These rails can be removed for users who prefer a cleaner and more streamlined appearance, or can be used to mount accessories to the rifle.

Unique serial number

Each VKS receives an individual incremental serial number, engraved on the receiver and visible inside the magazine well.

Available configurations

The VKS is available in several configurations:

• Spring-powered version
• HPA version (coming later)
• With full-size suppressor
• Without suppressor

All configuration are proposed in 3 different colors:

• Black with suppressor , SBA-VKS-01BK
  

• Black without suppressor , SBA-VKS-02BK
  
  

• FDE with suppressor, SBA-VKS-01FDE
  
  

• FDE without suppressor, SBA-VKS-02FDE
  
  

• OD Green with suppressor, SBA-VKS-01OD
  
  

• OD Green without suppressor, SBA-VKS-02OD
  
  

For players looking for a more compact and stylish configuration, we have made a 14mm CCW adapter , the Ash12 muzzle brake , and a VKS half-size suppressor

VKS user manual

VKS exploded views