KWA M4A1 Review

By:  Tim Seargeant

 
    The first time KWA made an AEG it was nothing really special, the G36 basically displayed KWA capability to go beyond gas blow back pistols.  The KWA M4A1 on the other hand is a huge leap forward in airsoft engineering, what KWA has done with the version 2 gearbox is astounding and should be the new standard to which all gearboxes are made.

    Months ago KWA announced that they were building an AEG with a gearbox that was capable of using a Lithium Polymer battery right out of the box.  Easier said than done right?  Well they did it.  We decided to test their efforts with an 11.1V 3200MaH LiPo battery; it held up great at 400 FPS with a fantastic rate of fire.  After putting out a few thousand rounds with that battery we decided that it was time to really test the internals with a 16V LiPo.  This battery has never been used in a gun longer than a few seconds because it keeps breaking pistons; even our fully customized Airsoft GI High Speed P90 only pulled off one BB before the gears stripped and the back end of the piston ripped off.  To our surprise the KWA M4A1 was able to successfully empty 8 high capacity magazines without breaking.  I should note that the BBs were completely ineffective, they were only traveling at about 150 FPS.  There are two possible explanations for this; as the BBs are traveling through the barrel they may be colliding with one another, or the battery is spinning the gears so fast that it is catching the piston on its way forward in which case there would be incomplete compression inside the cylinder.  Either way, we concluded that the 16V LiPo is useless with this gun, but it’s amazing that the gearbox can handle such abuse and still be in tact and operational.  This display of durability left us speechless, we were extremely curious to get inside the gearbox and see what KWA had done, so we got right to work.

    Once the gearbox is disassembled from the body the reinforcement on the front is in plain view, as is the extra screw at the top to hold the frame together.  At this point there is nothing to rant and rave about, but once we got the gearbox opened up completely we found a lot of surprises.  The first question we had to answer was, “What kind of piston did they use that can withstand such a battery?”  It was a black polycarb piston with reinforcing around the last 4 teeth.  This left us with a lot more questions because the design of the KWA piston seemed to mimic the Prometheus Hard Piston, but the Prometheus piston had reinforcements on all of the teeth and it still could not withstand the 16V battery in the Airsoft GI P90.  The KWA piston must be made of some special government issued polycarb or something because it is by far the most durable light weight piston that Airsoft GI has ever seen.  Next we took a careful look at the sector gear, which looked new and unused, and discovered that it was wider than normal.  That explains why none of the teeth broke off, with a wider surface area the energy exerted on each tooth is spread throughout.  All of the gears were a shade of dark silver which suggests that they are constructed of steel.  Another important feature to note would be the 8mm ball bearings that allow the gears to turn with a silky smooth fluidity.  Apart from the aforementioned internal parts the rest of the gearbox is put together with really high quality equipment.  The KWA M4A1 comes stock with a metal spring guide equipped with ball bearings.  On the front of that amazing piston is an Aluminum piston head.  The switch assembly is made of good quality plastic and the wires are carefully soldered to their connectors.  The final thing to note about the KWA M4A1’s gearbox is the air seal nozzle, it unique to this gearbox only, meaning aftermarket replacements will not work.  Why the nozzle is different is unknown at this time, its really nothing to be concerned about, the stock nozzle provides a really good air seal and it’s an item that rarely breaks.

    Let’s move to the outside now, at first glance the KWA M4A1 looks very similar to the SRC M4.  The gun is completely black, except for the orange tip, and I mean completely.  Every external part behind the flash hider is a shiny reflective black coat of paint, even the gearbox, hop up, and motor are all jet black.  The flash hider is the standard birdcage that comes with most M4’s.  The barrel is a solid two piece construction and it is held to the upper receiver with a real gun style delta ring.  The triangle front sight has the bayonet lug on the front bottom and a barrel mounted sling point underneath it.  Inside the top hand guard is a replica gas tube, completely useless for airsoft but it’s a nice touch of authenticity.  There is absolutely no play in the barrel or the hand guards and the delta ring is easy to maneuver, this is like a sigh of relief for Classic Army owners who sometimes need two people to get the hand guards off because the delta ring is so stiff.  The body is constructed of metal and the KWA logo can be seen laser etched into the left side of the magazine well.  On the top rail there is a plastic carry handle, even though it is plastic the color match is very close and the handle itself is very durable.  The functional charging handle opens the dust cover and reveals the two piece plastic hop up.  Even though the hop up is made of plastic and is two piece it provides a fantastic air seal.  At the rear of the lower receiver there is a sling mount for the left and right side of the body, and behind that is the 6 position LE retractable stock with another sling mounting point at the base.

    The KWA M4A1 is an airsoft engineering feat that has never been sought after before by a manufacturer.  There are players that spend hundreds of dollars customizing their gun and reinforcing it in preparation for a Lithium Polymer battery, and it is possible to a certain extent.  KWA has pushed up the bar and exceeded the performance capabilities of the version 2 gearbox with seemingly minor changes, and provided a true LiPo ready airsoft AEG.  KWA has set a new standard for quality, performance, and durability.  If KWA can keep producing high quality AEGs like the M4A1 then the future of airsoft is looking very bright.