Durable Custom M4 SOPMOD, 130m/s, AirsoftGuns, BY-039, BI-3981MDurable Custom professionally upgraded version of the electric airsoft gun M4 SOPMOD [BY-039/BI-3981M] with muzzle velocity up to 130 m/s. This is not a standard serial production in China or Taiwan, where it is not possible to devote much time and care to each weapon. Upgrade has been done by our company, which has more than ten years of experience and plenty of satisfied customers. The Durable Custom suggests that the weapon was drawn particularly on high emphasis of solidity and durability of internal parts weapons. Configuration requirements for a good performance, healthy rate of fire, excellent durability and reliability.
Identification Durable Custom suggests that the weapon was drawn particularly on high emphasis of solidity and durability of internal parts weapons. Configuration requirements for a good performance, healthy rate of fire, excellent durability and reliability. this metal gun comes from the latest edition, which has a newly processed metal body with functional dust cover. Modern type with metal M4 RIS handguard, tactical retractable Crane stock (6 setting positions) and removable rear sights on which it is possible to attach different scopes and red dots instead.
Gun was fitted by parts from SHS, which have become a world leader in AEG upgrades. The following components were used..
Complete cylinder set from the SHS:
CNC metal piston head with the bearing
SHS metal cylinder head M4
Polished stainless steel cylinder M4
Aluminum nozzle M16/M4 - 21.5 mm
Stress parts from SHS:
Precise piston with a steel teeth
A set of classic gears - standard (16:1)
Rotary spring guide for the gearbox v. 2
Performance parts from the SHS:
Long motor SHS - Torque
Precision 6.03 mm barrel
And the other:
Silicone Hop-Up rubber system
SHS delayer clip
Metal Hop-Up set M16/M4
Gilded T-Dean connector
Universal MOS FET switch kit - Type Standard
Original metal reinforced gearbox was modified by radii and metal chamber of gun was arching by rubber o-rings, which is intended for prevent premature rupture of the gearbox. This problem is not unco mmon for homemade upgrades and weapons of mass-produced in China or Taiwan and equipped with a strong spring. The weapon is equipped with a spring M110 and added cylinder set and good alignment is achieved performance up to 130 m/s. The weapon is luxuriously equipped with low resistance wiring and silicon MOS FET switch which is with strong springs absolutely necessary, but often it is underrated by manufactures and sellers. Including the charger and the battery, it is recommended to order types. See recommended accessories tab. The pack is supplied tactical sling, cleaning rod, Wind Up Hi-cap Magazine 300rds, tactical grip and 2pc covers on RIS rails.
|- notice -
|Battery and charger are not included.
|AEG Variant (EBB/NBB)
|7 mm, ball bearings, metal
|reinforced version 2 (7 mm)
|Inner Barrel Length
|Long SHS - hi-torque
|Muzzle velocity the measured
|130 m/s [427 fps]
|VB Li-Pol 7.4V, 2000mAh, 15C, CQB
|0.25 - 0.28 g