CYMA CM.508 M4A1 S-System AEG

CYMA
Code:
1,249.00 kr
  • 6.03mm Tightbore inner barrel
  • Alloy version 2 gearbox 
  • S-System/SIR 20mm railed handguard

If you're looking for an affordable beginner Airsoft gun with a unique look, the CYMA CM.508 M4A1 S-System AEG should be right up your street! This M4 AEG is battery-powered and constructed predominantly from ABS polymer with an alloy version 2 gearbox based on the Tokyo Marui design. This keeps the build light and easy to move with, ideal for younger skirmishers or those looking for something lighter than a full metal primary for late in the skirmish day. 

The alloy version 2 gearbox the CM.508 is based around is equipped with 18:1 standard ratio gears running on 8mm steel bushings, a type 1 cylinder, reinforced polymer compression parts and a quick change spring system. Also inside is a 6.03mm tightbore inner barrel and an updated rotary HOP-up unit, giving you above-average accuracy potential and the latest HOP-up unit design for M4/AR-15 AEG platforms. All internal parts are standard Tokyo Marui AEG spec, meaning the sky is the limit when it comes to upgrades later down the line!

On the outside, the CM.508 is ready for 20mm Picatinny accessories such as red dot sights, scopes, tactical flashlights, lasers and vertical grips, ready to be customised for the mission at hand. The barrel is threaded to 14mm CCW male, meaning suppressors and tracer units can be added for sneaky styling and an instinct-aiming advantage. If you want to try your hand at Airsoft skirmishing or target shooting without breaking the bank, the CM.508 M4A1 S-System AEG from CYMA is the most affordable way to do it!

Full description

Description

Our current batch of CYMA Sport AEGs are supplied with a USB Charger and an 8.4V 1100mAh NiMh Battery. While these items are perfectly functional, we recommend using a 7.4V 1300mAh LiPo battery and a LiPo Balance Charger for faster charging times, a longer lasting battery and improved performance. A brief reminder never to leave your battery on charge unattended and always use a Battery Safe Charging Bag

If you're getting kitted out for Airsoft on a tight budget and like a primary with a unique look, the CYMA CM.508 M4A1 S-System AEG Rifle is what you need! This lightweight polymer M4/AR-15 platform is part of CYMA's recently revamped "Sport" AEG range, offering unbeatable value for a competitive, skirmish-ready primary!

On the outside, the CM.508 is ready to rock with a SIR style 20mm Picatinny quad rail handguard and 20mm railed receiver, ready for your choice of mission essential accessories. The barrel has 14mm CCW male threading, ready for your choice of muzzle device. Whether you want to run a scope, red dot sight, suppressor, tracer unit, aiming laser, tactical flashlight or just a vertical grip, the CM.508 is ready to be clad with accessories for the elite look!

Made predominantly from high-density polymer but equipped with an alloy outer barrel and alloy version 2 gearbox, the CM.508 is surprisingly well-equipped for the price and is even better in the most recent version! Inside, you'll find 18:1 ratio steel gears running on steel 8mm bushings along with a 6.03mm tightbore inner barrel and rotary HOP-up unit, all of which are compatible with standard M4 AEG aftermarket parts. When we first received our CM. 508s years previously we were impressed and the latest version is even better!

Starting at the front, we can see a polymer birdcage flash hider mounted to the 14mm CCW male threading at the tip of the 14.5-inch alloy outer barrel. The outer barrel's 14mm CCW threading means the CM.508 is ready to be kitted out with a tracer unit for CQB specialists or a suppressor for the sneaky skirmisher, though the pre-installed birdcage device completes the military-issue look. If you find the pre-installed flash hider hard to remove, we recommend submerging it into warm water for a minute or two to loosen it and then attempting to unscrew it.

Moving along the outer barrel, we can see the military-style M4A1 barrel profile, complete with M203 grenade launcher mounting cutout. The front sight follows as we reach the handguard, constructed from polymer and replicating the real steel A.R.M.S flip-up front sight. The sight can be deployed simply by lifting it up and stowed again by holding down the circular button on the right side before folding it down. The presence of flip-up sights means you'll have a clearer sight picture when using a red dot sight or scope, ensuring you get a wide field of view and an unobstructed sight picture.

Following the front sight, we come to the handguard assembly which replicates the real steel A.R.M.S SIR, an upgraded handguard used by Green Berets and Navy SEALs during the early Global War on Terror era. The handguards are made from lightweight ABS polymer equipped with a monolithic 20mm Picatinny rail running along the top, with short rails at the 3, 6, 9 and 12 o'clock positions.

The extended top rail provides far more room on the receiver and handguard than most M4 rifles, meaning you can mount bigger scopes and even red dot sight and magnifier combos. Being a monolithic design means the rail extends all the way from the front to the rear, benefitting from a stronger design than comparable RAS handguards. 20mm Picatinny rails allow 20mm Picatinny accessories to be fitted wherever you need them, including vertical and angled foregrips, laser aiming devices, tactical flashlights, bipods and more!

Mounted to the left side of the handguard, we have our first sling point; a standard alloy footman loop compatible with a wide variety of sling types. This can be paired with the rear sling point on the sliding stock to fit a two-point rifle sling to take the burden off your arms or allow for easy transitions to a sidearm.

The handguard also serves as the battery compartment in this "front-wired" M4 AEG. To access the compartment, simply turn the polymer screw-style locks on each side by 270 degrees (to the rear of the side rails, next to the small embossed padlock symbol). Once turned, the locks should pop out but stay retained in the handguard, allowing the lower handguard section to slide forward and lift free. Inside, you'll find a mini-Tamiya battery connector to which you connect your battery.

The set includes an 8.4V 1100mAh NiMh battery and a basic USB charger, though if you're going for an aftermarket battery please ensure you're using the correct charger for your choice of battery. We recommend using a 9.6V 1600mAh NiMh with an NiMh charger for a better trigger response, rate of fire and battery life but the included 8.4V battery should get you going if you're on a tight budget. A quick reminder: never leave your battery on charge unattended!

Moving rearward we reach the receiver, a standard M4/AR-15 milspec design with a 3-position fire selector switch and all the details a proper replica needs. The receiver is constructed from high-density polymer with a matt black finish and features a unique serial number just above the trigger. The fire selector switch is located on the left side of the AEG and sits directly above the pistol grip to provide fast and easy access for right-handed shooters. The fire selector's 90-degree throw between modes makes it quick to operate but not too easy to accidentally knock it and end up in the wrong fire mode. Each fire mode is indicated with recessed text, reading "SAFE - SEMI - AUTO", just like a real M4A1 rifle.

At the centre of the left side of the receiver, we can find the "ping pong paddle" dummy bolt release catch which doesn't have a function in an Airsoft AEG but is included to keep the externals looking realistic. The bolt release is a separate part which is a nice touch to avoid the tell-tale signs that this is an Airsoft gun and not the real deal. Over on the right side of the receiver, we can see what is known as the forward assist button, located on the upper receiver behind the mock shell deflector. This button also has no function but serves to force the real M4/AR-15 bolt carrier into battery if it fails to close due to dirt ingress. The button can be pressed and is also a separate part, keeping things visually accurate to the real thing. 

The magazine release is on the right side of the magazine well and is ideally positioned to be pressed with the trigger finger from a firing grip for right-handed users. Left-handed users can use their support hand thumb to press the release, and this can be done quite fast with a little practice. The surface of the mag release is textured to provide the necessary gripping qualities, and is protected from accidental presses by the "magwell fence", a raised protrusion in the receiver which stops the mag release from catching on your gear as you move.

The CM.508 is packaged with a 300rnd High-capacity magazine which can be filled through the fill window on the top of the magazine body and tensioned via the winding wheel on the bottom. Wind the wheel 5-10 times or until you hear the noise change, after which you can insert the mag and get busy! If you notice feeding stop, wind the wheel again to continue shooting.

At the top rear of the receiver, you'll find the charging handle of the CM.508 which doesn't need to be pulled before the first shot. Instead, this serves to open the dust cover and retract the mock bolt carrier, revealing the rotary HOP-up adjuster inside. The adjustable HOP-up unit allows you to adjust the amount of backspin applied to your BBs and tune the CM.508 for your ammo weight of choice, looking for the flattest possible trajectory. 

We recommend using 0.25g BBs as they are great for both indoor and outdoor skirmishes. As part of our latest batch of CYMA Sport AEGs, the CM.508 improves over the earlier version with the rotary HOP-up design, the latest and greatest design for M4 AEGs offering improved accuracy and the ability to hold its setting under the vibrations of full-auto fire.

As we reach the rear, we come to the 5-position M4/AR-15 buffer tube, offering 5 adjustment positions for the pre-installed "Colt LE" style stock. Adjusting the stock is as simple as pressing the lever on the bottom and sliding it into your position of choice, accounting for almost any body type or loadout.

The LE stock was first introduced in the 1990s with the original M4, improving on the older XM177/CAR15 stock with extra sling options, a more comfortable cheek rest and a serrated butt plate for optimal traction in any weather conditions. The original sling slot for "strap" slings is present and at the toe, we have a footman loop for cavalry-style sling setups.

Inside, the CM.508 is very well equipped for the price, boasting full Tokyo Marui M4 AEG compatibility as a bonus. Inside, you'll find an alloy version 2 gearbox with a quick change spring system, 18:1 standard ratio steel gears running on 8mm steel bushings, reinforced polymer compression components and a type 1 cylinder.

Also inside is a 6.03mm tightbore inner barrel paired with the latest HOP-up unit design for the M4/AR-15 AEG platform, known as the "Rotary" type. The tightbore barrel improves accuracy potential and air-efficiency and the rotary HOP-up provides less side-to-side shot deviation for a tighter grouping downrange, especially in full-auto.

If you're eyeing up your first Airsoft AEG or need an affordable and reliable backup with a unique look, the CYMA CM.508 M4A1 RIS CQB AEG Rifle is ideal. With skirmish-competitive performance, the ability to add a plethora of accessories and upgradeability for a future-proofed setup, the CM.508 is a great value entry point into the world of Airsoft skirmishing!

Features

  • Airsoft AEG - Powered by a rechargeable battery
  • High density polymer build - Feels agile but not flimsy
  • 6.03mm Tightbore inner barrel - Great accuracy potential
  • 14mm CCW Male threaded outer barrel - Tracer/suppressor ready
  • M4/AR-15 A.R.M.S Style folding front sight post - Flip the front sight down for a clearer view down an optic
  • 20mm Picatinny SIR/S-System quad-railed handguard - Add a vertical foregrip, flashlight or laser
  • 20mm Picatinny railed receiver - Ready for a red dot sight or scope
  • Ghost ring iron sights - Flip up front and rear sights, rear sight is fully adjustable
  • 3 Position fire selector switch - SAFE - SEMI AUTO - FULL AUTO
  • Rotary adjustable HOP-up unit - Pull and hold back the charging handle to access
  • Realistic M4A1 receiver features - Dummy bolt release & forward assist button
  • Sling points front and rear - We recommend using the front sling point & the loops on the stock
  • 5-Position M4/AR-15 Buffer tube - Adjust the stock to suit your body type and preferences
  • LE stock pre-installed - Grippy serrated butt plate, low profile design with built-in sling point
  • 300rnd High-capacity magazine included - Plenty of BBs on tap!
  • Front wired: Mini-Tamiya battery connector - Recommended battery: 7.4V 1300mAh LiPo or 9.6V 1600mAh NiMh
  • Version 2 gearbox
    • Alloy shell
    • 18:1 Steel gear set
    • 8mm Steel bushings
    • Reinforced polymer piston
    • Reinforced polymer piston head
    • Type 1 Cylinder
  • Compatible with M4/AR-15 AEG magazines - Spares are plentiful!

Package Includes

  • CYMA CM.508 M4A1 S-System AEG 
    • 8.4V 1100mAh NiMh Battery
    • USB Charger
    • Cleaning/unjamming rod 

Specification

General

Weapon Construction External
Weapon Type
Assault Rifle
Over 18 Only Icon
Over 18
Yes
Icon UKARA - United Kingdom Airsoft Retailer Association
Defence / UKARA Required
Yes, No,
FPS Icon
FPS (Feet Per Second), using 0.20g BB
Approx. 328fps ± 10%, using 0.20g BB
Site Legal Icon
Site Legal, using 0.20g BB
Yes
Package
Included Items
Magazine
Skill Level Icon
User Skill Level
Starter
Patrol Base - Warning Icon
Warnings
Li-Po - Never Leave Charging Unattended
Li-Po - Only Use Approved Chargers
Li-Po - Charge in a Fire Safe Area

Weight and Dimension

Weight KG Icon
Weight (KG)
Approx. 1.7kg
Weapon Length Collapsed
Length (Collapsed)
77.5cm
Weapon Length Extended
Length (Extended)
85.5cm

Construction

Colour Wheel Greyscale
Primary Colour
Black
Two Tone Icon
Pre Two-Toned
No
Construction Icon
Construction
Polymer receiver, stock, buffer tube, handguard, flash hider & sights. Alloy outer barrel & internals.
Weapon Construction External
External Construction
Polymer
Alloy
Gearbox Icon
Internal Construction
Polymer
Alloy
Aluminium
Steel

Weapon Specific

Power Source Icon
Powered By
Electric
Blowback Icon
Blowback
None
Weapon Platform
Assault Rifle, M4 / AR-15 / M16, M4/AR-15 AEG, AR,
Magazine Style Icon
Magazine Style
Long Gun Magazine, Assault Rifle, M4 / AR Platform,
Fire Select Icon
Fire Selector
PatrolBase | Fire Select Safe
Safe
Patrol Base | Fire Select - Semi Automatic
Semi Automatic
Patrol Base | Full Automatic
Full Automatic
Weapon Safety Features Icon
Safety Features
Trigger Lock
Shooter Configuration Icon
Shooter Configuration
Right Handed
Weapon Configuration Icon
Weapon Configuration
Standard
Weapon Scale Icon
Weapon Scale
1:1
Suggested BB Weight
0.25g

Hop-Up

Hop-Up Unit Icon
Hop-Up Unit
Yes
Hop-Up Unit Adjuster Icon
Hop-Up Adjuster
Rotary
Hop-Up Unit Location Icon
Hop-Up Location
Behind the mock bolt carrier, accessible when the charging handle is pulled and held back.

Furniture

Weapon Furniture Icon
Furniture
  • Railed Handguard
  • Railed Receiver
  • Sliding Stock
  • Flip-Up Ironsights
Rail System Icon
Rail System
20mm RIS / RAS
Icon Stock Positions
Stock Setting
Sliding
Weapon Length Extended
Stock Positions
6 Position
Sight Type Icon
Sight Type
Iron Sights
Sling Plate Icon
Sling Options
Stock , Handguard ,

Barrel

Outer Barrel Length (in)
14.5''
Icon Thread Type
Outer Barrel Thread Type
Male
Icon Thread Direction
Outer Barrel Thread Direction
CCW (Counter Clockwise)
Outer Barrel Thread Size
14mm
Inner Barrel Diameter
6.03mm
Inner Barrel Length
363mm

Magazine Specific

Magazine Type
AEG, High Capacity,
Magazine BB Capacity
Approx. 300 Rounds
Magazine BB Fill Method
Fill Window
Magazine BB Fill Location
Top

Electric Gun Specific Information

Gearbox
Gearbox Icon
Gearbox Version
V2 Gearbox
Wiring Icon
Gearbox Wiring
Front Wired
Battery Specific
Battery Connector
Patrol Base | Icon | Mini Tamiya
Mini Tamiya
Included Battery
Battery Type
Ni-Mh
Battery Voltage
8.4V
Compatible Battery
Compatible Battery Type
Li-Po
Compatible Battery Configuration
Crane
Compatible Battery Voltage
7.4v

Product Testing Data

Notepad Icon
Test Description
328 FPS +/- 10%
Notepad Icon
Tested Using
0.20g ASG Blaster BBs
Notepad Icon
Test Date
04/12/2024

Related video

Size guide

Joule Charts

Special Instructions

These table can be used as a reference to see if the BB weight you are using will be over acceptable Joulage limits at some Airsoft Sites in the UK. To check if the weight can be used chrono your weapon using the BB you intend to use, and then compare it to the chart.

FPS, Power and Joule Limits can vary from site to site, so please get in touch with where you're going to play with in advance to avoid disappointment.

Suggested limits are based on Joulage Limit rules used Halo Mill: Proving Grounds, with a 350fps limit for Automatic Replicas, 400fps for Semi-Automatic Replicas, and 500fps for Bolt Action Replicas.

Tap the tabs below to open the relevant chart for your replica.

Suggested limits are based on Joulage Limit rules used Halo Mill: Proving Grounds, and is the equivalent of 350fps, using 0.20g BB resulting in an upper limit of 1.14j.

Velocity BB Weight (Grams)
FPS 0.20 0.25 0.28 0.30 0.32 0.36 0.40 0.43 0.45 0.50
250 0.58 0.73 0.81 0.87 0.93 1.05 1.16 1.25 1.31 1.45
260 0.63 0.79 0.88 0.94 1.00 1.13 1.26 1.35 1.41 1.57
270 0.68 0.85 0.95 1.02 1.08 1.22 1.35 1.46 1.52 1.69
280 0.73 0.91 1.02 1.09 1.17 1.31 1.46 1.57 1.64 1.82
290 0.78 0.98 1.09 1.17 1.25 1.41 1.56 1.68 1.76 1.95
300 0.84 1.05 1.17 1.25 1.34 1.51 1.67 1.80 1.88 2.09
310 0.89 1.12 1.25 1.34 1.43 1.61 1.79 1.92 2.01 2.23
320 0.95 1.19 1.33 1.43 1.52 1.71 1.90 2.05 2.14 2.38
325 0.98 1.23 1.37 1.47 1.57 1.77 1.96 2.11 2.21 2.45
328 1.00 1.25 1.40 1.50 1.60 1.80 2.00 2.15 2.25 2.50
330 1.01 1.26 1.42 1.52 1.62 1.82 2.02 2.18 2.28 2.53
335 1.04 1.30 1.46 1.56 1.67 1.88 2.09 2.24 2.35 2.61
340 1.07 1.34 1.50 1.61 1.72 1.93 2.15 2.31 2.42 2.68
345 1.11 1.38 1.55 1.66 1.77 1.99 2.21 2.38 2.49 2.76
350 1.14 1.42 1.59 1.71 1.82 2.05 2.28 2.45 2.56 2.85
355 1.17 1.46 1.64 1.76 1.87 2.11 2.34 2.52 2.63 2.93
360 1.20 1.51 1.69 1.81 1.93 2.17 2.41 2.59 2.71 3.01

Suggested limits are based on Joulage Limit rules used at Halo Mill: Proving Grounds, and is the equivalent of 400fps, using 0.20g BB resulting in an upper limit of 1.49j.

Velocity BB Weight (Grams)
FPS 0.20 0.25 0.28 0.30 0.32 0.36 0.40 0.43 0.45 0.50
250 0.58 0.73 0.81 0.87 0.93 1.05 1.16 1.25 1.31 1.45
260 0.63 0.79 0.88 0.94 1.00 1.13 1.26 1.35 1.41 1.57
270 0.68 0.85 0.95 1.02 1.08 1.22 1.35 1.46 1.52 1.69
280 0.73 0.91 1.02 1.09 1.17 1.31 1.46 1.57 1.64 1.82
290 0.78 0.98 1.09 1.17 1.25 1.41 1.56 1.68 1.76 1.95
300 0.84 1.05 1.17 1.25 1.34 1.51 1.67 1.80 1.88 2.09
310 0.89 1.12 1.25 1.34 1.43 1.61 1.79 1.92 2.01 2.23
320 0.95 1.19 1.33 1.43 1.52 1.71 1.90 2.05 2.14 2.38
330 1.01 1.26 1.42 1.52 1.62 1.82 2.02 2.18 2.28 2.53
340 1.07 1.34 1.50 1.61 1.72 1.93 2.15 2.31 2.42 2.68
350 1.14 1.42 1.59 1.71 1.82 2.05 2.28 2.45 2.56 2.85
360 1.20 1.51 1.69 1.81 1.93 2.17 2.41 2.59 2.71 3.01
370 1.27 1.59 1.78 1.91 2.03 2.29 2.54 2.73 2.86 3.18
380 1.34 1.68 1.88 2.01 2.15 2.41 2.68 2.88 3.02 3.35
390 1.41 1.77 1.98 2.12 2.26 2.54 2.83 3.04 3.18 3.53
400 1.49 1.86 2.08 2.23 2.38 2.68 2.97 3.20 3.34 3.72
410 1.56 1.95 2.19 2.34 2.50 2.81 3.12 3.36 3.51 3.90

Suggested limits are based on Joulage Limit rules used at Halo Mill: Proving Grounds, and is the equivalent of 500fps, using 0.20g BB resulting in an upper limit of 2.32j.

Velocity BB Weight (Grams)
FPS 0.20 0.25 0.28 0.30 0.32 0.36 0.40 0.43 0.45 0.50
250 0.58 0.73 0.81 0.87 0.93 1.05 1.16 1.25 1.31 1.45
260 0.63 0.79 0.88 0.94 1.00 1.13 1.26 1.35 1.41 1.57
270 0.68 0.85 0.95 1.02 1.08 1.22 1.35 1.46 1.52 1.69
280 0.73 0.91 1.02 1.09 1.17 1.31 1.46 1.57 1.64 1.82
290 0.78 0.98 1.09 1.17 1.25 1.41 1.56 1.68 1.76 1.95
300 0.84 1.05 1.17 1.25 1.34 1.51 1.67 1.80 1.88 2.09
310 0.89 1.12 1.25 1.34 1.43 1.61 1.79 1.92 2.01 2.23
320 0.95 1.19 1.33 1.43 1.52 1.71 1.90 2.05 2.14 2.38
330 1.01 1.26 1.42 1.52 1.62 1.82 2.02 2.18 2.28 2.53
340 1.07 1.34 1.50 1.61 1.72 1.93 2.15 2.31 2.42 2.68
350 1.14 1.42 1.59 1.71 1.82 2.05 2.28 2.45 2.56 2.85
360 1.20 1.51 1.69 1.81 1.93 2.17 2.41 2.59 2.71 3.01
370 1.27 1.59 1.78 1.91 2.03 2.29 2.54 2.73 2.86 3.18
380 1.34 1.68 1.88 2.01 2.15 2.41 2.68 2.88 3.02 3.35
390 1.41 1.77 1.98 2.12 2.26 2.54 2.83 3.04 3.18 3.53
400 1.49 1.86 2.08 2.23 2.38 2.68 2.97 3.20 3.34 3.72
410 1.56 1.95 2.19 2.34 2.50 2.81 3.12 3.36 3.51 3.90
420 1.64 2.05 2.29 2.46 2.62 2.95 3.28 3.52 3.69 4.10
430 1.72 2.15 2.40 2.58 2.75 3.09 3.44 3.69 3.86 4.29
440 1.80 2.25 2.52 2.70 2.88 3.24 3.60 3.87 4.05 4.50
450 1.88 2.35 2.63 2.82 3.01 3.39 3.76 4.04 4.23 4.70
460 1.97 2.46 2.75 2.95 3.15 3.54 3.93 4.23 4.42 4.91
470 2.05 2.57 2.87 3.08 3.28 3.69 4.10 4.41 4.62 5.13
480 2.14 2.68 3.00 3.21 3.42 3.85 4.28 4.60 4.82 5.35
490 2.23 2.79 3.12 3.35 3.57 4.02 4.46 4.80 5.02 5.58
500 2.32 2.90 3.25 3.48 3.72 4.18 4.65 4.99 5.23 5.81
510 2.42 3.02 3.38 3.62 3.87 4.35 4.83 5.20 5.44 6.04