Specna Arms M4 SA-B13

Overview

Specna Arms SA-B13 is based on the well-known M4 platform. Slightly improved in terms of design, this replica is intended for close-quarters battles. The materials used in its construction provide an advantage to the user due to its reduced weight.

Exterior of the Replica

Impressive.... We can only commend the gentlemen at Specna Arms for the quality-to-price ratio they offer with their replicas. The exterior of the airsoft replica is well-made, and the materials used are both durable and lightweight. Aluminum and aluminum alloys are utilized, significantly reducing weight and enhancing maneuverability. The design of the airsoft replica is both aesthetically pleasing and efficient. The front rail system mimics the KeyMod system. On the upper body, there is a standard rail running almost the entire length of the airsoft replica, allowing for the mounting of a wide range of optical sighting devices.

A large part of the airsoft replica is made of metal, while the ABS plastic elements include the grip and stock of the airsoft replica. The stock is adjustable with 6 positions and features a rubber pad for improved grip, and due to its considerable dimensions, crane batteries can be installed. The airsoft replica is equipped with a classic folding sighting system, allowing for the use of other sighting devices. Note that to operate the sighting system, the button on the left side must be pressed.

To add a touch of realism, the manufacturers have installed a system that simulates an active bolt catch, making hop-up adjustment much easier. The airsoft replica can be secured with a sling using the sling swivel positioned above the grip, with access to this attachment system available on both sides of the replica. There is also a support point for the replica at the back of the rail system, which is a QD type system. Note that the included sling is not intended for supporting the airsoft replica.

Interior of the Replica

The airsoft replica is equipped with a nearly standard version 2 gearbox, the only difference being the ability to replace the spring without opening the gearbox casing, but don't get too excited, the gearbox still needs to be removed to perform this operation. Regarding the internals of the replica, we can say they are of high quality. The piston, its head, and the cylinder head are made of polycarbonate, while the gears are made of quality metal. The shimming of the airsoft replica is well done, and the sound of the functioning gearbox is good. The motor of the airsoft replica is standard but successfully engages the internal mechanism, with a consumption of only 10-11A, indicating it is a well-optimized gearbox. This performance is certainly aided by the 8 mm bearing gears.

The hop-up chamber is metal, and the adjustment is located inside the ejection port. It can be accessed by operating the charging lever of the airsoft replica. The assembly is good even though the inner barrel has a diameter of 6.08 mm. When correctly adjusted, the hop-up allows the replica to achieve considerable engagement distances. The velocity of the airsoft replica is approximately 115-120 meters per second measured with 0.20g BBs. The package also includes a spring that provides approximately 90-95 meters per second.

Power Supply

The package of the airsoft replica includes a 9.6V 1100 mAh mini crane battery that mounts in the stock. It is recommended not to use batteries larger than 9.6V as the toy may malfunction. LiPo batteries can be used but not exceeding 7.4V. Only use quality BBs and do not reuse BBs, as this may damage the airsoft replica.