GBB or AEG? A never-ending debate among airsofters. There is no question that gas replicas offer greater realism when firing. KJ Works presents version 3 of its M4 GBB. While it brings many internal improvements, the new low handguard stands out, and in a colour that will draw a lot of attention. And once you try it... Oh my! Where to start; the need of cocking before firing, the weight of the magazines, the recoil feeling in each shot... Would you like to know more? Ok then, here is the review.

Handguard

If there is a feature which stands out at first sight in this third version of the model it is the handguard, not only due to its spectacular copper brown colour, but also because of its design. It follows the premise of the URX III by Knight Armament by offering a floating handguard, with small Picatinny sections at the beginning and at the end, with none at the central part, where usually they are not really used (although it has an M-LOK to be able to add attachments if needed). This reduces the weight and profile of the model, and so the grip becomes more comfortable. Besides, the thumb of the hand grabbing the handguard does not interfere with the sights no matter how low the profile you are using is.

Muzzle 

The muzzle is also one of the striking elements, a modern design with which KJ breaks away from its usual style. It simulates a silencer that is housed inside the handguard. The piece only measures 3 cm, of which 2 are inside the handguard, and only one protrudes, but due to its shape, it can be guessed that the silencer continues inside the handguard. Since it is a merely an aesthetic element in airsoft, with it they manage to reproduce the effect without making you take any unnecessary extra weight.

Magazine

The magazine is of C8 type, a rifle developed by Colt Canada (formerly Diemaco) and which has been used by different units in northern Europe, including the UKSF. Its main external feature is the external fluting; very comfortable in airsoft to improve the grip and speed in fast reloads. It has a capacity for 30 BBs, which are not fed from the top as a normal AEG magazine, but from the side as a GBB pistol. In addition, the gas goes in the magazine, so the weight exceeds 400 g (instead of just a little over one hundred as we are used to in AEG’s). Disassembling the magazine is simpler than its subsequent assembly, so we do not recommend it, apart from not being necessary beyond satisfying our curiosity. It has reinforced walls, whose thickness makes it hold the gas very well and that it is less affected by the temperature at which we use it. In fact, we have had it in the office for several months and it still holds the last gas load.

Sights

It has the KA-01 sights that we already saw in the KC-02, a folding model that unfolds when you press a large button on the top, and which collapse by just pressing them down. A very comfortable system due to its operation and thanks to the fact that the front sight has an optic fibre point that will help us to align them even in low lighting conditions.

Stock

It has a stock like the Bravo Company Milspec M4 stock Gen. 2. A really light option, very easy to use and with two possible belt hooks (to which we must add the ambidextrous ring holder at the end of the stock, attached to the body). It is true that it may be simpler than other models you can find, but of course simplicity is something that often works best when playing airsoft. 

Fire selector

If you have never played with an M4 GBB you will be struck by the operation of the fire selector, since it is “blocked” with the replica uncocked and once you cock it, it will be easy to change to the firing position you need.

GBB operation

The first thing you need to do to fire a GBB is to insert a full magazine, pull the cocking lever and you will be ready. When we run out of BBs, the internal lock will be locked waiting for the new magazine. But even inserting it, you will have to press the release of the bolt catch to continue firing. An exception is when you change magazine before firing all BBs, since in that case the lock is not blocked and you can insert a new magazine and continue firing. Something to keep in mind when playing to gain extra seconds when reloading, could you keep track of the BBs fired with each magazine? With an average speed of 430 FPS with 0.20 g BBs, this is rather surprising due to the feeling when firing it, and you can fire around five magazines per gas load. This obviously depends on ambient temperature and rate at which you fire.

GBB Features

Internally it has a GBB style barrel (different from AEG’s due to its final cut to fit with the hop’s rubber) but with its own KJ Works design. A 250 mm barrel and an inside diameter of 6.04 mm; these replica measurements are chosen by many riflemen. The hop chamber, while very simple, is also of their own design. The hop’s rubber also has a unique design, which will make it harder to find replacements. However, it works very smoothly, although to play in cold weather we recommend moistening it a bit with silicone spray to soften it, as it may be a bit hard otherwise. The roulette controller is located inside the ejection port, only in the upper part.

An GBB M4 is always something that draws attention in an airsoft field usually ruled by AEG, and combined with a design as modern as this (yes, we still love that handguard) is impossible to go unnoticed. In addition, it has all the experience of a manufacturer that has become one of the big ones in terms of GBB guns, so it creates high expectations that are met and exceeded.