Description

Golden Eagle M4 RIS CQB Gas Blowback Rifle (Metal – Black – MC6624M)
Specifications
 

Brand: Golden Eagle
Type : Gas Blowback 
Length : 680mm – 760mm (Collapsable)
Weight : 2200g
Velocity(Fps) : Approx 330 with .20g BBs and Green Gas
Inner Barrel Length : 260mm
Inner Barrel Diameter : 6.03±0.01
Material :  Aluminium Alloy Barrel, Buffer Tube, Rail and Receiver, Nylon Polymer Stock and Pistol Grip
Fire Mode : Safe/Semi/Full Auto
Magazines: Golden Eagle, S&T, G&P,  GHK, Western Arms (WA) System Compatible Magazines both Gas and CO2
Magazine : 38 Rounds PMAG (Polymer Outer shell) (Low Cap Magazine)
Hop-Up : Adjustable 
Barrel Thread Type : 14mm CCW 

Features
Golden Eagle continue to prove themselves worthy of any airsofter’s armoury, producing great quality airsoft replicas at a competitive price point, capable of going up against some of the bigger and more premium brands. Their newly improved gas blowback M4 range is truly impressive. This particular variant, the MC6624 is their replica Colt M4 CQB rifle, used worldwide most notably by the US Military and is a popular choice for airsofters due to its pop culture following in movies and video games, size handy in both CQB and woodland play, and the customizability thanks to the ample rail space it has. 
The gun has an aluminium alloy outer barrel and receiver and 20mm RIS rail handguard system for the mounting of lights, lasers and grips. The upper receiver also features a rail for optics and can be used instead of or in conjunction with the removable rear sight. The stock and pistol grip are made of a tough and durable nylon reinforced polymer, as is the magazine’s outer shell. These magazines are PMAG styled, and an update to the rifle, they are a bit more simple in design to the older metal STANAG type one that Golden Eagle used to include, making them a bit more reliable, and lighter; handy for carrying several for gameplay. 
Because they function more realistically than AEGs, gas rifles are more realistic dimensionally and compatible with more real parts, making them highly customisable. For example, some real Magpul furniture would make an excellent addition to one of these. The rifle is based on the Western Arms design which was the original gas blowback M4/AR system, utilised by a myriad of other manufacturers including GHK, G&P, Viper Tech, EB Tech, Inokatsu, to name a few. It is widely regarded by many as the most realistic GBB system available. Opening it up by popping the rear receiver pin, you’ll notice that the fire control parts are just like a real AR, even down to the shape of the hammer. The bolt carrier is realistically sized and weighty, giving the rifle a hefty recoil impulse. 
Though the WA system is an older and more dated system for airsoft, with other brands being more innovative to functionality within the purpose of airsoft, like the MWS system; the WA system is still relevant and widely utilised by various manufacturers and therefore still being updated and improved upon. For Example, one of the weaknesses of GBB M4s in general tends to be their bolt catch, which inevitably wears away and stops functioning and needs replacing. Golden Eagle provides a steel bolt catch out of the box, mitigating this issue. And giving you a reliable last round bolt hold open, signalling it’s time to reload and preventing dry fire. 
This GBBR is compatible with Western Arms magazines, G&P WOC, GHK magazines and any other GBB AR magazine designed for the WA system, although it will work best with Golden Eagle branded magazines. The Golden Eagle M4 CQB is a great choice for anyone wanting to dip their toes into the world of  gas blowback rifles for the first time, as well as the more experienced player who’s looking for the ultimate realism.
Please note that just like the real rifle, you cannot manipulate the safety fire selector unless the rifle is cocked.
 
Note* When filling the magazine with gas, there’s a few things you can do to help keep it working properly and ensure they last as long as they should. 

Hold the magazine with the fill valve facing up. (usually on the bottom of the magazine, sometimes on the back)
Insert the nozzle of the gas canister and push straight down. Gas shouldn’t spurt out of and around the valve, it should go straight into the magazine.
Listen for the hiss inside the magazine as it fills. It’s usually quick and then stops. When it stops, stop.
With a pistol mag fill 3-5 seconds worth of gas. With an extended or rifle mag around 7-10 seconds. This gives you enough while preventing you from over filling it. When you over fill, usually the first shot releases too much if not all of the gas, which cools down quickly and prevents the gun from working properly.
Never ever ever release the gas from the magazine via the knocker valve with the mag out of the gun, the only thing that should press that button is the firing pin.
And Finally, always store a bit of gas in the magazine. Maintenance gas (Abbey 144a) or green gas that contains silicone lubricant (most do) This will keep the seals tight and stop them from drying out and failing. 

So to recap that… Gas in, fill downwards, just a few seconds, only release it by firing it out (dry firing with no BBs is fine) and always leave some or put some in for storage. Gassed mags are happy mags.