Boyi D-Boys M4 SIR Airsoft Gun AEG Metal

The Boyi D-Boys M4 SIR is a full metal gun, which includes a monster of a rail. The rail extends over the entire top of the gun. It also has additional rails on the sides of the forend, and on the bottom of the forend. Additionally, a vertical foregrip is included. Features also include a folding rear and front sight.

As there are many people interested in the mid-level airsoft guns, and more and more “Marui Clones” and “Chinese knockoffs” are hitting the shops, I decided that AP could benefit from knowing more about them. I have been interested in the S-System and decided to pick up the BOYI version of this gun from www.airsplat.com

This is a great gun for an entry/mid level airsoft player. In comparison to Tokyo Marui, I would recommend it as a comparable alternative. It comes with all the components necessary to use it right out of the box. Two areas where I was disappointed were the plastic flash hider, and the light weight plastic butt stock. It is upgradable, but may not withstand high FPS springs.

• 330 FPS with decent rate of fire.
• Plastic receiver is a durable plastic.
• Alan type receiver pins
• Metal rails, very durable.
• Metal front and rear rifle sights
• Heavy gears. The gears seem more durable than stock Tokyo Marui gears.
• Metal hop-up chamber
• Removable sling mounts on stock and foregrip.
• Systema clone piston.
• AEG Gear box comes very well lubricated.
• Top of barrel threads off for suppressor
• Spring guide soft plastic, but it does have a aluminum base, better than stock Tokyo Marui spring guide rod.
• Metal trigger stop inside gear box (plastic on Tokyo Marui, CA, and ICS).

• Plastic flash hider comes glued on. Difficult to remove, but not impossible.
• Retractable LE style but stock is made from very light weight plastic, kind of flimsy.
• Plastic bushings. (pictures are shown with replacement metal bushings.)
• Front sight does not completely lock in the upright position, but it is pretty sturdy.
• Gear Box Cylinder is not ported. This is not always a bad thing, but with a longer barrel it can create suction and lose FPS.
• AEG Gear box is very light. May not be the best for upgrading to high velocity, not recommended for a metal piton head.
• Upper receiver is proprietary for this gun, not compatible with other AEG front ends.
• Rail system is not compatible with other guns unless custom modification