M4A1, BI-3281 Metal Gearbox

M4 carbine - information taken from Wikipedia.org

The M4 and its variants fire 5.56x45mm NATO ammunition (or .223 Remington ammunition) and are gas-operated, air-cooled, magazine-fed, selective fire firearms with a multi-position telescoping stock. Original M4 models had a flat-ended telescoping stock, but newer models are now equipped with a redesigned telescoping stock that is slightly larger with curvature at the end. The M4 is similar to much earlier compact M16 versions, such as the 1960s-era XM177 family. Some of those visual designs are obvious in both weapons, however most of the similarities are not very noticeable.

As with many carbines, the M4 is handy and more convenient to carry than a full-length rifle. The price is slightly inferior ballistic performance compared to the full-size M16, with its nearly 6" (15 cm) longer barrel. This becomes most apparent at ranges of 300 yards and beyond. Statistically, however, most small-arms engagements occur within 100 yards. This means that the M4 is very much an adequate weapon for the majority of troops. The marginal sacrifice in terminal ballistics and range, in exchange for greatly improved handling characteristics, is usually thought to be a worthwhile compromise.

While the M4's maneuverability makes it a candidate for non-infantry troops (vehicle crews, clerks and staff officers), it also makes it ideal for close quarters battle (CQB). The M4 was developed and produced for the United States government by Colt Firearms, which had an exclusive contract to produce the M4 family of weapons through 2009; however, a number of other manufacturers offer M4-like firearms. The M4A1, along with the M16A4, have mostly replaced the M16A2; the U.S. Air Force, for example, plans to transition completely to the M4. The M4 is also the standard rifle for U.S. Air Force Security Forces members whether at home station or deployed abroad. They maintain a yearly qualification on it.

The United States Marine Corps has ordered its officers (up to the rank of lieutenant colonel) and Staff Non-commissioned officers to carry the M4A1 carbine instead of the M9 handgun. This is in keeping with the Marine Corps motto, "Every Marine is a rifleman." United States Navy corpsmen will also be issued M4A1s instead of the M9.

BI-3281 Replica

This M4A1 replica had bean made of werry durable ABS. Use of metal gearbox greathly extends life spawn of the replica in compare to the full ABS wersion's avaible on the marcket. This solution also allow's for use od other standard AEG parts wich increses overall preformence.

Replica is powerd by battery wich is easy to mount and may be fited within cople of moments in to the front grip. This solution prevent's the battery from accidental demage during skirmish.

Build in folding stock allow's for seting it's lenght right for eavery user as well as for adjusting overall lenght of the replica according to the combat zone requirements.
Transport grip placed on top of the body may be detached uncovering 22 mm RIS rail system wich allow's for mount of any kind of the sight or scope.

Set includes:

- BI-3281
- Hi-cap Magazine
- Battery chardger
- Battery

Technical details:

Product Name:	M4A1 Carbine BI-3281
Manufacturer:	BOYI/DBOYS
Warranty:	12 months
Velocity [FPS] It is the spped of bb, while its leaving the innerbarrel of replica. This speed is measured in FPS (Feet Per Second). 1 FPS = 0,3 ^m/_s 1 J = 99 ^m/_s 1 J = 326,7 FPS :	320
Propultion Replicas have spring, electric or gas propultion. Spring models need to reload after each shot (pull back the lock) to enter the ball into the chamber. At the same time it pulls spring back, to be able to give a shot. Electric replicas depends on the battery, whereby the engine drives the whole gearbox, and a gas models, push the BB by gas, which loads in magazine (in these replicas ther is not spring). :	Electric propulsion
Gearbox version Indications v2, v3, v6 does not mean the level of advance, but only shape of gearbox skeleton which was used and selected by the manufacturer depending on the capabilities of the body of the replica. For example, a models of the M4/M16 family, MP5, have a v2 gearbox, while the AK family have gearbox v3. :	Gearbox v2
Type of fire:	Single, auto
Made of:	ABS
Lenght [mm] The length of the replca is measured between the two most distant points of each other. Different models have several of these values, because of its design allows to increase or decrease it length (eg. folding stock or extended flash hider). :	700 / 780
Innerbarrel length [mm]:	363
Weight [g] This is a value that includes the weight of the replica, magazine and other accessories that are include in set without a battery, charger, cleaning rod, etc., etc. :	2194
Battery [V] Battery voltage is responsible for the frequency of shots. It must be remembered that, the stronger spring is in its replica, the higher voltage must have the battery, because the motor that drives the whole mechanism needs more energy to stretch the spring. :	8,4
Battery Capacity [mAh] Battery capacity determines the time, which it accumulated enough energy to work gearbox. The greater capacity, then replica will shoot longer. :	1100
Type of battery NiCd rechargeable battery is characterized by high efficiency current-carrying capacity, but there are disruptive effect on memory. Should be unloaded and loaded in the full cycle, ie, it is recommended to fully discharge, and after unloading must charge the battery immediately without leaving it for a long time in a discharged state. NiMH batteries have a higher self-discharge over time and shorten the life - on the other hand, they earn about 30% more capacity. :	Ni-Mh
Magazine type:	Hi-Cap magazine
Magazine capacity [pcs]:	300
Hop-Up Hop-Uup system is used for overclocking bb during the shot (putting it in rotation), through which, it extends its flight path. Acting laws of physics make that bb lift up, while the gravitational force take it down. Appropriate adjustment of Hop-Up, will compensate for these two factors, which result in long and straight flight for longer distance and be greater focus shot (to improve accuracy). :	Yes, regulated
Blow Back Blow back is a simulation system of the cocking lever - it imitates the work of it as the equivalent sharp. This system raises the realism and adds a lot more experience during shooting. :	No