Patrol Base
Product code:
  • PB Custom Build
  • Electronic Trigger
  • HBI 4'' Handguard

An Airsoft 6mm BB Gun, custom built by Patrol Base with unique custom parts, based on the Scorpion Evo 3 A1 Airsoft AEG by ActionSports Games in Denmark. Just like its real-steel counterpart, the Gun features a Heavy Duty Polymer Receiver, Stock, and Pistol Grip with Alloy Handguard, Charging Handle, Flash Hider, Outer Barrel and Internals.

Full description


The weapon has been highly modified for use with the custom HB Industries Handguard, with a modified Outer Barrel Assembly, Shortened Barrel, Rear Wired Gearbox, and Modified Receiver Design. The Handguard is a Real Steel Handguard designed for the real thing, and features a multitude of modern features, with its lightweight design and MLOK Rail Panels for adding extra attachments. Due to the nature of the Handguard, the weapon has been modified to allow the battery to be stored inside the Receiver, by first Rear-wiring the Gearbox, and then modifiying the Upper Receiver Plates to allow the battery to be stored above the Gearbox, underneath the rail. The Outer Barrel has also been shortened, along with the Inner Barrel, which is modified and pinned in place for a solid hold. The weapon as standard features a multitude of advanced features, which are made possible by the internal MOSFET which has been custom designed for the Scorpion, which allows for a Safe / Semi / Three Round Burst / Full Auto Fire selector. The weapon also features an Electronic Trigger for an instantaneous response, and Mag Empty Detection which prevents the weapon from firing when you run out of ammo. The Gearbox also features a Quick Change Spring System allowing you to change the FPS of your weapon quickly for the Game Site you are playing at. This is the perfect purchase for any Airsoft Skirmisher who is looking for the ultimate CQB weapon, which not only outperforms most weapons on the field, but is also way beyond competitive at outdoor skirmishes.

Other Features: 

  • Patrol Base Custom Build AEG
  • Built In-House by our team of Workshop Technicians
  • Official Real Steel HB Industries Custom 4'' Handguard
  • Custom Modified Rear Wired EVO Handguard
  • Custom Modified Rear Battery Storage Compartment
  • Custom Modified Upper Receiver Plates
  • Custom Modified Outer Barrel Assembly
  • Upgraded to Deans Battery Connectors
  • Fitted Upgrade Spring
  • Modified Shortened Barrel
  • Build Costs Included
  • Quick spring change design
  • Internal Error Detecting MOSFET Computer System
  • Electronic trigger
  • Folding stock which locks in place
  • Full length top rail for large Sight, Scope and Magnifier
  • Three round burst capability
  • Mag empty detection which stops firing when magazine is empty
  • Functional Bolt Lock
  • Removable Sliding Stock
  • Reduce BB loss hop unit
  • Functional charging handle
  • Ambidextrous Design, making it usable by both Left and Right Handed Shooters
  • Fast reload
  • Battery monitoring
  • Failure detection
  • Crisp electronic trigger response
  • CNC Processed Gearbox
  • Quality Wiring
  • Built entirely in Europe
  • Receiver Forward sling mount can be switched to either side
  • Constructed from the same high-strength mil-spec polymer as the real steel weapon
  • Alloy V2 Parts Compatible Gearbox
  • Adjustable Hop-Up unit for increased Range and Accuracy
  • 6.03mm 147mm Tightbore Barrel
  • Threaded Outer Barrel for attaching Evo Thread Converter for Suppressors and Tracer Units
  • Supports all of the Evo Attachments Range
  • Branded:
    • 'CZ SCORPION EVO 3 A1'

Package Includes:

  • CZ Scorpion Evo 3 A1 K Custom - Black
  • Ironsights
  • Magazine
  • User Manual

Special Instructions:

Patrol Base Custom Warranty

This weapon is custom built by Patrol Base, and as such we handle the warranty. We will match the 12 month warranty which ASG Provide, for up to 12 months from the date of purchase.

Battery Warning

Please ensure that you use the battery recommended for the weapon. In this case the: NUPROL - 11.1v 1200mAh 20c EVO K Modified LiPo Battery which has been modified to fit the weapon. This is to ensure peak performance, as well as fitting.

Upgrades and Repairs

Should you need advice or information regarding the Scorpion Evo, or indeed any Airsoft Item, please feel free to get in contact with our ASG Certified Workshop Department by giving them a call on: 01484 644709.

Quick Change Spring

Please ensure that when removing the Gearbox Quick Release Spring Screw a standard Allen Key is used, as using a Ball Type Allen Key Head will damage the nut. 

LiPo Use
If you use a LiPo please ensure it is removed after Skirmishes as the battery will be trickle drained over time breaking the battery.

Battery Insertion
To insert the battery first unfold the stock, slide the battery into the receiver, then connect the battery, with the wires and connectors facing outward.


The following is a short guide to troubleshooting your Scorpion Evo. The Electronic Control System in the Scorpion Evo can detect the following problems:

  • Low Battery
  • Short-Circuits
  • Mechanical Failures (Broken Gears etc.) 

In the event of a failure the Evo will sound two audible beeps and then stop functioning.

  1. 1. First, disconnect the battery.
  2. 2. Check the battery if the battery is fully charged or damaged, and then try another battery.
  3. 3. Check for short-circuits, looking for water penetration, if so, place the gun in a dry place and let it dry out.
  4. 4. Check the wiring for damaged or exposure.
  5. 5. Check for mechanical damages (This should be carried out by a skilled Airsoft Technician).

If the problem persists please contact us on: 01484 644709 and ask for the Workshop.

If the gun does not sound any beep when connecting the battery or the gun stops functioning without sounding any beeps:

  1. 1. Check for disconnected motor plugs
  2. 2. Check for motor burn out

If no audible sounds are emitted this usually means there is a problem with the motor or its connection as the motor emits the sound.

Please note that it is safe to try reconnecting the battery several times as the Electronic Control System protects the gun from surge and spikes.



Weapon Construction External
Weapon Type
Submachine Gun
Over 18 Only Icon
Over 18
Icon UKARA - United Kingdom Airsoft Retailer Association
Defence / UKARA Required
Yes, No,
FPS Icon
FPS (Feet Per Second), using 0.20g BB
Approx. 345fps ± 10%, using 0.20g BB
Site Legal Icon
Site Legal, using 0.20g BB
Included Items
  • Magazine
  • Instruction Manual
  • Ironsight Set
Skill Level Icon
User Skill Level
Experienced Player
Patrol Base - Warning Icon
Patrol Base (Evo K)

Weight and Dimension

Weight KG Icon
Weight (KG)
Approx. 2.06kg
Weapon Length Collapsed
Length (Collapsed)
Weapon Length Extended
Length (Extended)


Colour Wheel Greyscale
Primary Colour
Colour Wheel Greyscale
Secondary Colour
Two Tone Icon
Pre Two-Toned
Construction Icon
Polymer exterior. Alloy handguard, charging handle & outer barrel assembly.
Weapon Construction External
External Construction
Gearbox Icon
Internal Construction

Weapon Specific

Power Source Icon
Powered By
Blowback Icon
Weapon Platform
Submachine Gun, CZ Scorpion Evo,
Magazine Style Icon
Magazine Style
CZ Scorpion Evo
Fire Select Icon
Fire Selector
PatrolBase | Fire Select Safe
Patrol Base | Fire Select - Semi Automatic
Semi Automatic
Patrol Base | Full Automatic
Full Automatic
Patrol Base | Burst
Weapon Safety Features Icon
Safety Features
Trigger Lock
Shooter Configuration Icon
Shooter Configuration
Weapon Configuration Icon
Weapon Configuration
Weapon Scale Icon
Weapon Scale
Suggested BB Weight


Hop-Up Unit Icon
Hop-Up Unit
Hop-Up Unit Adjuster Icon
Hop-Up Adjuster
Hop-Up Unit Location Icon
Hop-Up Location
Pull charging handle to reveal hop adjust inside dust cover


Weapon Furniture Icon
  • Railed Handguard
  • Folding Stock
  • Railed Receiver
  • Ambidextrous Magazine Release
  • Ambidextrous Fire Selector
  • MLOK Rail System
  • Ambidextrous Safety
Rail System Icon
Rail System
MLOK Rail System
Icon Stock Positions
Stock Setting
Sliding , Folding ,
Weapon Length Extended
Stock Positions
2 Position
Sight Type Icon
Sight Type
Light Enhancing Open Iron Sights
Sling Plate Icon
Sling Options
Stock , Handguard , Receiver ,


Icon Thread Type
Outer Barrel Thread Type
Icon Thread Direction
Outer Barrel Thread Direction
CCW (Counter Clockwise)
Outer Barrel Thread Size
Inner Barrel Diameter
Inner Barrel Length

Magazine Specific

Magazine Type
Medium Capacity , AEG,
Magazine BB Capacity
Approx. 75 Rounds
Magazine BB Fill Method
Speed Loader
Magazine BB Fill Location

Electric Gun Specific Information

Wiring Icon
Gearbox Wiring
Top Wired
Battery Specific
Battery Connector
Patrol Base | Icon | Deans
Suggested Battery
Suggested Battery Type
Suggested Battery Configuration
Suggested Battery Voltage

Product Testing Data

Notepad Icon
Test Description
Notepad Icon
Tested Using
Blaster 0.2g BBs

Delivery & returns

Delivery & Postage

Here at Patrol Base we ship all around world, with delivery not only to the UK, but to most of the EU and select Worldwide locations as well. We provide a working day by road service via our handpicked courier services, simply buy your Airsoft guns with us and we'll have them delivered directly to your door.

For more information and to see the country we deliver please check out our Delivery Information Page.


Below are some rough postage prices for orders. Please note these are subject to change, and are only a rough guide. For more accurate postage estimate please use the Postage Calculator at the basket.

UK Standard



UK Next Day



Highlands / Islands






* Please note that Scottish Highlands, Islands and EU post prices can vary wildly. Prices range from £8.99, up to £29.99, so please ensure you refer to the Postage Calculator at the basket for the lowest possible price.


We want you to be absolutely happy with our products and services, so we provide the simple Patrol Base guarantee: if on receiving your item you are unhappy with your item for any reason then simply send it back to us. We will replace or refund the item.

You can return any item for any reason whatsoever, even if you have just changed your mind, within 14 days of receipt of the order. This is in addition to your rights under the Consumer Protection (Distance Selling) Regulations 2000.

For more information on returning products, and how to do it please visit our Returns Policy Page.

Finance options

Looking to buy an Airsoft replica, but don't want to drop all your money at once? Perhaps you want to spread your payments over time to keep a backup of money, or perhaps you simply can't afford the hit right now and want to spread it over time? In any case you can spread your payments to take away the pain of the initial hit of the purchase of a replica, or give yourself the ability to spend that little bit more and get that rifle you've always wanted!

Want to know more about Airsoft Interest Free Finance?
You can check out our Airsoft Finance Info Page for more details >

Here at Patrol Base we have partnered with Omni Capital Retail Finance, allowing you to buy now pay later with ease.

You can select finance during the payment process which will take you to the Omnicapital portal and allow you to complete a credit check at your leisure. Once your finance is accepted you will be able to complete your order and wait for the goods to arrive!

Wondering how much it's going to cost?
Check out the examples below.

Looking to make the jump from BB guns to Airsoft, but don't want to save up to buy your entire loadout? Your time has come!

Airsoft replicas are leaps and bounds ahead of BB guns, but can sometimes carry a heavy price tag. You can spread the cost with us to save the strain on your wallet to allow you to buy your entire loadout at once, rather than piece by piece. Play now, pay later.

Want to know exactly why Airsoft Replica are so much better than BB Guns? Check out our BB Guns Page.

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