Cyma CM621 M4 Keymod Mosfet/QD Spring M4/AR15 AEG Rifle in Black

Cyma CM621 M4 Keymod MOSFET/QD Spring M4/AR15 AEG Rifle in Black

Key Features

- Lightweight reinforced polymer M4/AR15 platform 

- 11-inch KeyMod handguard with full-length top accessory rail 

- MOSFET-equipped electrical system with quick-change spring setup 

- Full-metal, fully upgradeable Version 2 gearbox 

- 6-position adjustable Crane-style stock 

- Metal outer barrel assembly and buffer tube 

- 14mm CCW threaded muzzle for compatible accessories 

- Battery and charger included 

Light enough to throw around in CQB, long enough for general field work, and built around the familiar V2 gearbox – the CM621 is a straightforward M4 that covers a lot of ground.

Description.

The Cyma CM621 M4 Keymod MOSFET/QD Spring AEG takes the familiar AR15 layout and puts it into a lightweight, practical package. The upper and lower receivers use reinforced polymer, while metal is retained for components including the outer barrel assembly and buffer tube. The result is an electric rifle that keeps the controls and handling of an M4 without carrying the extra bulk of a full-metal receiver. At around 1.8kg according to one of the supplied specifications, it's particularly easy to manoeuvre during longer games.

As a general-purpose Rifle, the CM621 sits neatly between a tiny CQB build and a long field-focused AR. Its adjustable Crane stock lets you shorten the airsoft gun when working around buildings, then extend it when you want a more relaxed shoulder position outdoors. That flexibility makes sense for a first Airsoft AEG, but it's equally useful for an experienced airsofter after a lighter backup or project gun.

Moving from the front backwards, the CM621 has a 14mm CCW threaded muzzle. That's the standard you'll see on a huge number of airsoft replicas, giving you plenty of options for compatible tracer units, mock suppressors and alternative cosmetic muzzle devices.

The 11-inch polymer KeyMod handguard keeps weight down while providing mounting options for compatible accessories. A full-length upper rail runs along the top of the gun, giving you space for a red dot, scope or PEQ-style accessory. The supplied rear sight is a flip-up SCAR-style unit, so you've still got a straightforward aiming option without immediately needing to add an optic.

The upper and lower receivers are made from injection-moulded polymer and include an enlarged trigger guard. It isn't trying to imitate the weight of a full-metal service rifle, and that's arguably one of the CM621's useful qualities. If you've ever spent a full skirmish day carrying an unnecessarily heavy BB Gun, you'll know that shaving weight from the receiver and handguard can be rather welcome by late afternoon.

At the rear, a metal buffer tube supports the six-position Crane-style stock. This gives you a useful range of adjustment for different arm lengths, clothing and tactical equipment. The stock also provides battery storage, keeping the power source out of the way while maintaining the conventional M4 layout. An ambidextrous rear sling point is fitted too, handy whether you run your sling from the left or right side.

Internally, the CM621 is based around a full-metal Version 2 gearbox. That's good news for maintenance because the V2 is one of the most common gearbox formats in airsoft. Parts availability and technical knowledge are widespread, so you're not dealing with some strange proprietary gearbox when the time eventually comes for servicing or upgrades.

The supplied product information also specifies a MOSFET and quick-change spring system. The MOSFET handles electrical switching within the AEG, while the QD spring arrangement makes accessing the main spring less involved than on older gearbox designs. A long-type motor provides the drive, and the rifle offers the expected safe, semi-auto and full-auto fire settings.

Hop-up is adjustable, allowing you to tune BB backspin for a flatter flight path. There is a discrepancy in the supplied barrel specifications: one section lists an approximately 400mm inner barrel, while another gives 328mm. Magazine capacity is similarly listed as both 350 rounds and 300 rounds. Rather than pick whichever number sounds better, we'd treat both figures as batch or specification variations unless confirmed on the individual gun.

The additional information lists output at approximately 1.3 joules, equivalent to around 377 FPS using a 0.20g BB, with manufacturing and measurement tolerances potentially affecting the figure. As always, chrono the rifle before skirmishing and make sure it falls within your site's power limits.

The CM621 ultimately makes most sense as a versatile, uncomplicated M4. It's light, adjustable and easy to accessorise, but underneath it still uses the familiar metal V2 gearbox architecture. Add the MOSFET, quick-change spring arrangement and included battery and charger, and you've got a practical AR-style package that can comfortably move between CQB-style layouts and general outdoor skirmishing.

Other Great Features are,

Reinforced injection-moulded polymer upper and lower receiver 

Enlarged trigger guard 

11-inch polymer KeyMod handguard 

Full-length top accessory rail 

Flip-up SCAR-style rear sight 

Metal outer barrel assembly 

Metal buffer tube 

Six-position adjustable Crane-style stock 

Ambidextrous rear sling point 

MOSFET-equipped electrical system 

Quick-change spring arrangement 

Full-metal Version 2 gearbox 

Adjustable hop-up 

14mm CCW muzzle thread 

In the box:

- Cyma CM621 M4 Keymod AEG Rifle in Black 

- M4-style high-cap magazine 

- Battery 

- Charger 

- Manual 

Specifications

Manufacturer: Cyma 

Model: CM621 

Platform: M4 / AR15 

Power system: Electric AEG 

Gearbox: Full-metal Version 2, fully upgradeable 

MOSFET: Yes 

Spring system: Quick-change / QD spring 

Motor: Long type 

Fire modes: Semi-auto, full-auto and safety 

Hop-up: Adjustable / variable 

Inner barrel: Listed as approximately 328mm-400mm in the supplied specifications 

Magazine capacity: Listed as 300-350 rounds in the supplied specifications 

BB calibre: 6mm 

Receiver: Reinforced polymer 

Handguard: 11-inch polymer KeyMod 

Outer barrel: Metal 

Buffer tube: Metal 

Stock: 6-position adjustable Crane style 

Muzzle thread: 14mm CCW / negative 

Battery connector: T-Plug according to the supplied additional specification 

Stated power: Approximately 1.3 joules / 377 FPS with 0.20g BBs 

Length: Supplied specifications list approximately 740-850mm depending on stock position 

Weight: Approximately 1800g 

Colour: Black 

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Sku :

211889