- MOSFET Inside
- Microswitch Trigger
- Quick Change Spring
Featuring a Microswitch Trigger, MOSFET and Quick Change Spring system with a tough Nylon Fibre exterior, the CYMA CM.621 is possibly one of the greatest out-of-the-box guns on the market for the money.
Fast Delivery
Delivery & Postage
Here at Patrol Base we ship worldwide, delivering 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.
Estimates
Below are some rough postage prices for orders. Please note these are subject to change and are only a rough guide. For a more accurate postage estimate please use the Postage Calculator at the basket.
UK Standard
£6.95
Approx.
UK Next Day
£8.95
Approx.
Highlands / Islands
£24.99*
Approx.
Saturday
£14.95
Approx.
* Scottish Highlands, Islands, and EU post prices can vary wildly. Prices range from £8.99 to £29.99, so please ensure you refer to the Postage Calculator at the basket for the lowest possible price.
Returns
We want you to be delighted 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.
Description
The CYMA CM.621 M4 KeyMod AEG is an M4 based design which offers a lightweight and tough KeyMod Rail System with 20mm RIS adaptors included for your choice of attachment type. It has a world of features out of the box which would be unheard of in most competing models in the same price range, and offers excellent value for money. With a MOSFET, Quick Change Spring, and reinforced Polymer externals, this AEG is the perfect starter gun.
The front of the AEG has a 14mm CCW Thread underneath the Bird Cage Flash Hider which will allow you to install Supressors, Tracer Units, Muzzle Brakes and more. Simply unscrew the grub screw from the Flash Hider and twist to remove. The Handguard is a KeyMod Rail System which comes included with side and lower 20mm adaptors, to give you flexibility in the type of attachments you can use. The Top 20mm Rail runs the full length of the Handguard and down to the back of the Receiver, which is ready for Sights and Scopes to attach, and is also where you will find a set of Flip Up Ironsights which can be removed if you don't want them. At the rear of the Receiver you will notice an Ambidextrous Sling Plate, which means that you can attach a Sling from either side of the Gun, depending on whether you're Left or Right Handed. The stock is a Sliding Crane Stock design and houses your Battery, connected to a Deans Connector. To access the Stock, simply squeeze the tabs on the Butt Plate and pull it away as well as the blanking plate underneath. We recommend either a 9.6v 1600mAH NiMH Crane Battery or 7.4v <2000mAH Crane LiPO Battery for the best fit.
Deep inside the CYMA CM.621 there is a MOSFET to protect the Electrical Components of the AEG, as well as a Microswitch Trigger which is very pleasant to use. The benefit of a Microswitch Trigger is much faster response from the gun, as well as removing the chance of burnt-out Trigger Contacts from a traditional design. The gun has a Quick Change Spring system which lets you change the Main Spring in seconds, once the Gearbox has been removed from the Receiver. This is an amazing feature for Airsofters who play at lots of different sites with varying Power Limit rules, and need to quickly change the FPS of their gun. Please note that technical skills are still required to remove the Gearbox from the gun. The gun has an Adjustable HOP Unit which will apply backspin to your BBs, and potentially increase effective range when combined with a Heavyweight BB (0.25g+) and the correct settings on the Adjustment Wheel. To make changes to the HOP, pull back the charging handle and look inside the dust cover to access the Adjustment Wheel.
Included in the box is an Alloy 300rnd High Cap magazine which is filled from the top via the fill window and wound from the bottom with the clockwork wheel to feed BBs. If you're looking for the ideal starter gun to get you on your way to Airsoft skirmishing, and/or are looking for fantastic value out of the box, then the CYMA CM.621 is just that.
Features
- Microswitch Trigger
- MOSFET Installed
- Quick Change Spring
- Tough Nylon Fibre Polymer
- Full Metal Gearbox
- Alloy Outer Barrel Assembly
- Alloy Buffer Tube
- Rear Wired / Deans
- 14mm CCW Thread
- 300rnd High Cap Magazine
- Flip-Up Ironsights
- Perfect Starter Gun
- Excellent Value for Money
- Sliding Crane Stock
- Fast Trigger Response
- KeyMod Railed Handguard
- 20mm Receiver Rail
- Ambidextrous Sling Plate
- Adjustable HOP
- Gear Style HOP Adjust
Package Includes
- CYMA CM.621 M4 KeyMod Airsoft Rifle
- 300rnd High Capacity Magazine
Specification
General
|
Assault Rifle
|
---|---|
|
Yes
|
|
Yes,
No,
|
|
Approx. 315fps ± 10%, using 0.20g BB
|
|
Yes
|
|
Magazine
|
|
Starter
|
Weight and Dimension
|
Approx. 2kg
|
---|---|
|
74cm
|
|
82cm
|
Construction
|
Black
|
---|---|
|
No
|
|
Alloy outer barrel assembly, magazine, buffer tube and trim. Polymer handguard, receiver, pistol grip and stock.
|
|
Polymer
Alloy
|
|
Polymer
Alloy
|
Weapon Specific
|
Electric
|
---|---|
|
None
|
|
AR, M4 / AR-15 / M16,
|
|
STANAG, M4 / AR Platform,
|
|
Safe
Semi Automatic
Full Automatic
|
|
Trigger Lock
|
|
Right Handed
|
|
Standard
|
|
1:1
|
|
0.25g
|
Hop-Up
|
Yes
|
---|---|
|
Gear
|
|
Behind mock bolt when charging handle pulled to the rear
|
Furniture
|
|
---|---|
|
20mm RIS / RAS , KeyMod ,
|
|
Sliding
|
|
6 Position
|
|
Iron Sights
|
|
Buffer Plate
|
Barrel
|
Male
|
---|---|
|
CCW (Counter Clockwise)
|
|
14mm
|
Magazine Specific
|
High Capacity, AEG,
|
---|---|
|
Approx. 300 Rounds
|
|
Fill Window
|
|
Top
|
Electric Gun Specific Information
Gearbox
|
V2 Gearbox
|
---|---|
|
Rear Wired
|
|
Yes
|
|
Yes
|
Battery Specific
|
Deans
|
---|
Compatible Battery
|
Ni-Mh
|
---|---|
|
Crane
|
|
9.6v
|
Product Testing Data
|
315FPS
|
---|---|
|
ASG Blaster 0.20g BBs
|
|
27/09/19
|
Detailed Power Tests
FPS
FPS, using 0.20g BB
|
Approx. 315fps, using 0.20g BB
|
---|
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.
This table should be used for reference, and cannot be used to check one weight against another, as the weight of the BB affects the power.
In order to check if the BB can be used with your replica chronograph using the weight you wish to use and then compare it against the table.
Every time you change weights you will need to re-chrono and check against the table. This is not a conversion chart between weights.
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 |