More and more aftermarket parts for the Tokyo Marui SOPMOD M4 recoil AEG are dripping onto the market and now Dytac brings us a broad variety of outer barrel lengths in silver and black.
Many other external parts can add to the tactical effectiveness of your weapon as well as just making it look good but it is barrel length that forms the backbone of your weapons aesthetic. With an M4 receiver, it is the difference in barrel length that defines it as a rifle, carbine, CQB assault weapon or an SBR (short barreled rifle).
This 7.5 Inch version is about as short as an M4 can realistically get (any shorter and a real gas block would not be functional which is not realistic), making an M4 an SBR weapon. Such super short weapons short change the power of your AEG so you will need a stronger spring to compensate.
A short barrel also open up your firing cone making it less accurate with greater spread at range thus also shortening your effective range. Another side effect of shortening the barrel and stepping up the spring to compensate is that the weapon gets louder.
For the trade off of power and accuracy, you get agility. Although it maintains the weight of an M4, an SBR is smaller then many SMGs giving you a weapon that can be handled much more easily in tight quarters. Effectively speaking, M4 assault rifle firepower in a large pistol format.