Kingdom of Airsoft Ltd
We are a worldwide leading specialist in all electric Airsoft platforms.
From Tokyo Marui to Jing Gong, from Systema to Double Eagle and everything in between.
We offer repairs and custom upgrade packages for AEGs, AEPs, Electric Shotguns, DMRs and more.
We also offer repairs and upgrade packages on all Tokyo Marui products and most Bolt Action rifles.
Frequently Asked Questions
There are a few things that we are asked on a regular basis, so here we aim to provide a fairly comprehensive one-stop-shop for all of the things new and experienced Airsofters might like to know.
Drop us a line with any questions at all and we'll add them to this list for future reference.
Please note, this is a work in progress.
1. What is the best gun for ‘x’ amount of money
This is a very interesting question and one that changes many times each year with the release of new platforms by established manufacturers and the emergence of new players on the scene wishing to make a splash.
There are many aegs that offer superb value for money in an all around package but for the sake of brevity, I shall initially restrict the answer to the Armalite platform as this is the most popular but will expand this over time.
The specific answer to the question must be narrowed down to enable an single answer. There are many different reasons to buy any given aeg over all the others so I shall define some categories first.
1) Best all around gun on a shoe-string ie. <£150
The Cyma AK series and G&G Combat Machine series are excellent choices for beginners or those on a tight budget
2) Best all around gun for a medium budget ie. <£300
My personal favourite here would be the WE M4 aeg
3) Best all around gun with no budget restrictions
When money isn’t a problem, you don’t have to worry about the internals so choose the platform with the best bodywork and go from there.
Real Sword, Inokatsu, VFC, G&P, LCT, E&L or even a ground-up build are excellent choices here.
My favourite bodywork is made by Madbull, with the JP Rifles Competition receiver set and OmegaX RIS topping that list.
2. What are the best upgrades for ‘x’ amount of money
I’ll answer this one by going into the most popular upgrades and upgrade packages that I do on the guns I work on. I’ll assume that the usual tuning has already been done or will be done so I can focus on actual parts; so before any of these recommendations would come: Cleaning, Shimming and Regreasing.
Probably the best upgrade for any given aeg, is a Sorbothane Pad.
It has a number of benefits while keeping it’s price very low and is probably the best value for money upgrade out there, at £5.
It corrects the Angle of Engagement, quietens the sound of the piston hitting the cylinder head and absorbs a large portion of the shock of that impact - which in turn greatly lessens the likelihood of the shell cracking.
The next upgrades on my list are usually recommended together as they compliment each other wonderfully. Again, virtually every aeg on the market can benefit from this selection:
Simple MOSFET with Genuine Deans Ultra Connector
High Torque Neo Magnet Motor
The MOSFET protects the trigger contacts from degradation due to electrical arcing and has a lower electrical resistance than the mechanical trigger so you’ll also see a slight rise in RoF and trigger response.
The ones I use also come with a high quality wiring loom, which will further amplify the above benefits. If you finish that off with a Genuine Deans Ultra connector, you’ll have removed all of the most common electrical bottlenecks which will allow the system to operate as efficiently as it can.
A good quality, High Torque Neodymium Magnet Motor will spin up and stop faster than any other motor. They have a much wider efficiency band so they can pull a much larger load before starting to struggle.
This makes them ideally suited for all forms of high performance upgrades, be they high speed, high response or high power.
An R-Hop is the first upgrade to be considered when range, accuracy and consistency are required.
After the Sorbothane Pad, this is my most popular upgrade with slightly over two thirds of all builds having one installed.
These three upgrades, along with a Service to cover the Sorbo Pad and general tuning, are what I call a mid-range upgrade package.
Virtually every aeg released to date would benefit from this selection.
3. What is an R-Hop
The R-Hop is the true next-generation hop-up system.
It is a concave, rubber-compound patch that is installed in the hop window of an inner barrel.
There are surrounding modifications to the barrel, hop rubber and chamber which are required to give optimal performance.
When installed correctly it provides a much longer contact area to impart backspin on the bb.
It is capable of applying more backspin in an even manner. This results in a much greater amount of potential backspin which in turn allows you to effectively use much heavier ammo.
Due to the law of the conservation of momentum, the heavier ammo - if an equivalent amount of backspin can be applied - will travel further than lighter ammo in almost every build.
The R-Hop matches the shape of the inner barrel so the BB is held in the center of the barrel instead of slightly to one side.
The end result is a system that can float bbs to much greater ranges with much greater accuracy and consistency than traditional hop systems are able to.
Contrary to popular accounts, the R-Hop is fully adjustable once installed however care should be taken when adjusting the system as it is possible to apply too much hop and jam the ammo in the chamber.
This can be prevented from happening during the installation stage by using a smaller buffer to apply the pressure but it may limit the maximum usable weight of ammo.
4. What is the best ‘tightbore’ barrel
There are many categories that a barrel can be judged on so ‘best’ is a rather nebulous term.
The primary function of an inner barrel is to contain and direct the air pressure generated by the gearbox behind the BB.
For maximum power efficiency, you’d want a very tight inner bore and a length that allows your chosen weight of ammo to continue accelerating until the very end of the barrel.
If a BB slows down while inside the barrel, any imperfections can affect the flight path of the BB to a greater degree.
Imperfections are bain of consistency and tight groupings so the ideal barrel would be as tight as possible, as long as needed and have a perfect inner bore finish.
We’ve seen no real evidence that the inner bore diameter specifically affects the groupings when all other variables are controlled for.
The main problem with super tight barrels is they can cause jams if the barrel and ammo are not completely clean.
To this end, we generally recommend a balanced approach to the inner bore diameter and opt for 6.02mm in most builds.
Brand wise, our go to choices for top-end barrels are EdGI and Airsoft Philosopher.
Brands like PDI, Lambda, ZCI and Prometheus all make decent barrels at varying price brackets.
5. What barrel length should I use to gain maximum range and accuracy
Range is a factor of power output, ammo weight and backspin.
Your power output, measured in Joules (or commonly fps) essentially sets the maximum range any RIF can achieve for any given weight of ammo.
Heavier ammo conserves both its forward and angular momentum so not only will it go further regardless of hop, it will conserve any backspin applied so the magnus effect will last longer and extend the range even closer to the maximum potential.
The effect of barrel length on range is minimal. The main advantage length brings to the table is that it is easier to utilise more of the compressed air generated by the gearbox. The barrel will contain and direct more of the air for a longer time allowing the BB to reach a higher power level.
Of course, many countries and sites have maximum power levels so the RIF cannot gain power forever, there is a limit.
What this allows is to use a weaker spring but achieve the same power output through efficiency increases. A weaker spring will put less stress on the motor and battery, leading to a faster trigger response, less power drained from the battery and less heat generated by the motor.
The effects of barrel length on ‘accuracy’ are even more minimal than the effects on range.
Accuracy is a factor of overall consistency, ammo consistency and ammo weight. Heavier ammo requires more energy to change its flight path so groupings will always be better with heavier ammo.
Each level of power output will have its own ideal ammo weight, providing a balance between range, groupings and time-to-target. There’s not much use using 0.45g ammo in a sub 1J gun to see pinpoint accuracy if the target can see the BB coming and has several seconds to step out of the way.
The inner bore finish of the barrel is much more important on the groupings but even less so than the ammo weight and quality and the method of backspin.
It’s recommended to use the highest quality barrel for the best groupings, for example EdGI and Airsoft Philosopher, but only after all other considerations have been optimised.
6. How do I stop gas mags leaking
Gas magazines generally leak when the rubber o-rings sealing the various different parts are not being fully compressed against the edges of where they are situated.
This can be caused by a number of issues; dry o-rings, poor quality o-rings, poor quality castings on the parts, loose valves or even temperature differences.
Every screw-in valve will feature several o-rings internally and externally so if the valve is tight enough (a little tighter than finger-tight, about 0.8Nm of torque if you can measure it) the most common solution is to apply some oil.
Liquid silicone oil of a medium viscosity is the safest, Superlube make some excellent silicone oil that is ideal for gas magazines.
If the o-rings are not dry and there are no casting imperfections, they may simply be the wrong size.
Companies like Lee’s Precision Engineering supply kits with various sizes of gas magazine o-rings that are easy to swap in.
7. Do airsoft suppressors actually work
Have someone clap next to your ear.
Now cover your ear with a towel and have them clap again.
Notice the difference in sound?
This is exactly how airsoft suppressors work, they slow down and absorb the sound waves that are created by the compressed air quickly escaping from behind the BB once it leaves the barrel.
Matching the volume of air to the exact weight of ammo and barrel length used can also negate this sound but that’s much harder.
An airsoft suppressor does nothing to mask the sound of the gearbox, good tuning and component choice are your friends there.
8. What is a MOSFET, why do I need one and what are the different types
In Airsoft, the term MOSFET refers to more than just the literal name.
A MOSFET specifically is a solid-state switch, meaning that it can turn on and off with no moving components. Its use in Airsoft requires a few additional components to allow it to work, we commonly call this group of components a ‘MOSFET’ but really it’s a Fire Control Unit or FCU.
A standard Airsoft gearbox will have a mechanical trigger that moves a shuttle with a metal front end towards metal contact plates, each one being hooked up to a side of the electrical circuit. Much like a light switch.
The problem with this setup is that as the shuttle nears the contacts, the voltage is high enough that the air gap between them will ionize and power will jump across just before they make full contact. This ‘arcing’ creates intense heat at a very small point which gradually wears down the contact plates leading to various issues before total failure.
An FCU takes this high power away from the mechanical switch assembly and handles it through the MOSFET where there are no moving parts so no arcing can happen.
The other supporting components allow the MOSFET to turn on when the mechanical switch assembly is used as normal, just without the arcing as only a tiny voltage travels across the contacts.
More complex FCU systems feature microprocessors and additional microswitches to electronically detect the trigger, fire selector and gears. These units totally replace the existing mechanical switch assembly and allow full control over the firing of the RIF.
The only downside to an FCU is the added complexity. A mechanical switch assembly is simple and effective, though prone to its own problems, for example semi-auto lockups.
Simpler FCUs are available which hook in to the mechanical switch assembly but they lack the advantages of a full trigger-replacement unit.
There is no correct answer to which FCU is best or whether to use one at all though there is no doubt that using one will unlock higher levels of performance that simply cannot be achieved with a mechanical system.
9. What are all the parts in a gearbox called and what do they all do
-This holds all of the internal components in place. It has to manage all of the stress generated by every part.
-These support the gears and allow them to turn freely without wearing out the gearbox shell
-The gears take the rotational energy from the motor and reduce the speed while increasing the torque. They generally consist of the Pinion gear (on the motor), the Bevel gear, the Spur or Step gear and the Sector gear. The Sector gear has one half with teeth to pull back the piston and one half without to allow the piston to travel forward while the gear continues to spin in one direction.
-The trigger assembly is a switch usually on the positive line from the battery. When the trigger is pulled, a shuttle with a metal block is pushed to bridge the gap between two metal contacts, one coming from the battery and the other going to the motor.
A mechanical safety lever usually sits in or next to this assembly to physically block the trigger when the selector plate is moved to the safe position
Trigger & Spring
-The physical trigger the user pulls to activate the motor and cycle the gearbox. A spring is used to reset the trigger once it is released
-The cylinder contains air from the ambient environment to be compressed to propel the BB.
-The cylinder head seals one end of the cylinder to direct the compressed air forward behind the BB. It has a static nozzle to support the ‘Air Nozzle’.
-The air nozzle sits on the end of the cylinder head nozzle and reciprocates to allow BBs to feed up in front of it (when it is retracted) before pushing them before in to the hop chamber.
-The piston is pulled back by the sector gear and pushed forward by the main spring when it is released.
-The piston head is attached to the piston and supports the piston-head o-ring which seals against the cylinder to compress the air that propels the BB.
-The main spring pushes the piston
-Linear springs have an even spacing between each coil so the power curve increases linearly
-Non Linear springs have weaker and stronger portions with closer and wider coils. This allows for a lower initial stress which increases progressively as the piston is pulled back.
Spring Guide & Bearing
-The spring guide supports the rear portion of the main spring so it can be evenly compressed.
They often feature a bearing to allow the main spring to rotate with less friction as it is compressed. This increases the lifespan of the spring and can improve consistency.
Tappet Plate & Spring
-The tappet plate is attached to the air nozzle and pulls this back to allow BBs to feed up in front of it. The tappet spring pulls or pushes the tappet plate forward to load the BB in to the hop chamber. The tappet plate is pulled back by a cam on the sector gear.
Cutoff Lever & Spring
-The cutoff lever and spring is how a gearbox achieves semi-automatic fire mechanically.
The cutoff lever sits underneath the trigger shuttle and when the trigger shuttle is pushed forward by the trigger, the shuttle cutoff sear on the side of the shuttle is positioned above the cutoff lever. The cutoff lever is activated by a cam on the sector gear so when the gears complete one cycle, the lever is lifted and pushes the trigger shuttle up and off the main trigger.
A spring on the trigger shuttle pulls the shuttle out of the contacts, breaking the electrical circuit and turning the motor off.
When the RIF is set to full-auto, the cutoff lever is lifted above the shuttle sear before the trigger is pulled so it can never disconnect the shuttle.
-Shims are used to position the gears and ensure they do not rattle or rub against each other.
-The selector plate is moved by the fire selector lever. In the safe position, the safety lever is lifted to block the main trigger. In the semi-auto position, the safety lever is lowered but the cutoff lever remains under the trigger shuttle.
In the full auto position, the cutoff lever is pushed so it is lifted above the shuttle before the trigger is pulled.
-The safety lever blocks the main trigger from being pulled when raised by the selector plate
Anti Reversal Latch
-The anti reversal latch (ARL) prevents the gears from rotating in the wrong direction
-The wire carries the power from the battery to the motor to allow the motor to turn and power the gearbox.
-The battery connector features two contacts (positive and negative) that plugs in to a matching connector on the battery. The most common plug types are mini-Tamiya and Deans Ultra (often called T-Plugs)
-The motor tabs are generally female spade connectors on the positive and negative wires that attach to the motor and allow power from the battery to flow to the motor
Motor & Pinion Gear
-The motor is usually a DC brushed 3-pole motor with two internal permanent magnets.
When power is applied to the motor tabs, it flows through the brushes to the commutator on the rotating armature. This energises copper coils, turning them in to electro-magnets. These magnetised coils repel from one permanent magnet and attract to the other, causing the armature to rotate. Just before the coils reach the magnets they are rotating towards, a new segment on the commutator reaches the brushes and powers up the next coil, keeping the armature rotating until the power is turned off.
A pinion gear is attached to the end of the armature axle to drive power through to the bevel gear.
10. What is AoE
AoE stands for Angle of Engagement.
It refers to the angle at which the first tooth of sector gear meets with the first tooth of the piston.
The first teeth of the gear and piston are generally referred to as the ‘Pickup’ teeth.
The AoE is usually adjusted to prolong the life of both components.
This is because the position of the meeting of teeth, or ‘Pickup position’ is generally not optimal.
In most stock gearboxes, the pickup teeth meet at an angle where the edge of the sector pickup tooth meets the edge of the piston pickup tooth.
This concentrates all of the stress to a single point, multiplying the stress and therefore the chance of failure.
In a stock gearbox, for example a Tokyo Marui, running on an average battery (9.6v NiMH 1400mAh) this is not much of an issue as the stresses are fairly low.
Once you start upgrading the gearbox to extract higher levels of performance, the chances of component failure increase so every effort should be made to ensure optimal operation and therefore reliability.
The object of adjusting the AoE is to make the pickup teeth engage each other flat-face to flat-face. This distributes the pressure over a larger area which reduces the force acting on any given point of the surface, which in turn reduces the chance of premature component failure.
The way this is achieved is by forcing the piston to sit further back in the gearbox using spacers.
The most popular way to space the piston back is to use a Sorbothane buffer pad to space the piston back almost all of the way and fine tune it with thin plastic shims (if required) between the piston and piston head.
11. What is Short Stroking and what is it used for
Short Stroking is the practice of removing teeth from the gear that pulls back the piston: the Sector Gear, and usually the same teeth from the piston.
It is done to shorten the stroke of the piston in order to allow it to return to the ‘rest’ or neutral position at the front of the gearbox in less time.
By shortening the stroke however, the power output is also lowered so Short Stroking is usually done in tandem with fitting a higher power spring to compensate.
This also helps increase the speed of the forward motion of the piston.
The reason a faster return rate is desirable is to ensure the sector gear engages with the piston in the correct position.
Failure to do so usually leads to premature wear of the gear and piston teeth or in extreme cases, complete failure of one or both. This problem is called Premature Engagement.
Premature Engagement becomes more of a problem in High Speed builds so this is a common countermeasure.
This common pairing has led to the propagation of the myth that Short Stroking by itself significantly increases the Rate of Fire; which it does but imperceptibly so, as the gears can spin up for slightly longer before hitting any resistance.
What it does do, is give a much snappier trigger response.
12. What is Sorbothane
Sorbothane is a brand of rubber compound with some useful properties.
It is impact resistant and retains its shape very well but can absorb a large percentage of shock from an impact.
This makes it uniquely suited to absorbing the shock of a piston hitting the front of the gearbox while still consistently spacing the piston into the optimal position for perfect engagement (AoE).
13. What lubes to use and where
14. Battery chemistry and explanations
15. The difference between hop rubber types (soft/hard)
Softer rubbers can apply more backspin to the BB because but are more likely to deform under high pressure levels.
Harder rubbers retain their shape and so give better consistency but cannot apply as much backspin as they are more ‘slippery’.
Balancing the hardness of the rubber can be tricky but for UK power levels I have found the Prometheus Purple rubber to give the best all-round results.
16. Dispelling common myths
17. What sort of performance is actually achievable
18. How do you lock a gun to semi-auto (mechanically and electronically)
19. Advantages and disadvantages of Gas and Electric including weather efficiency etc
20. Beginners guide to choosing an Imitation Firearm. Sniper / assault / gas / electric / aep / hpa / shotguns / grenades etc etc
21. Value for money analysis.Cost v benefit analysis of AEG internals? i.e. Is there a price point below which you are likely to buy shite? And what is that price point? Is there a price point above which you are not really getting much more value for your money? Are there particular models of AEGs which don't fit into this hypothesis? e.g. Quality internals for a good price or super-shite and also super-expensive.
22. Bearings vs Bushings
23. What is the best wire gauge and brand
24. Do you need a fuse
In reality, not really.
What do I recommend? Always run a fuse.
A fuse is a safeguard. Setting the discussion on the different types and efficiencies of fuses aside for a minute, it is designed to trip in the event of something going wrong and prevent damage to more expensive components.
There are many designs of fuses.
The standard Glass fuse, Blade fuses, Thermal self-resetting fuses and intrinsically self-protecting circuits.
The first two are very similar, in that they are both designed with a small piece of metal that heats up and burns out when a sustained current of a given amount passes through it.
It is generally easier to replace blade fuses as they are designed to be gripped firmly without breaking and are more readily available in suitable current ratings.
Glass and blade fuses are fine in low powered airsoft guns but are limited by a high internal resistance which can lower the Rate of Fire by allowing less current through.
Self resetting fuses generally have a much lower internal resistance and do not require replacement once tripped.
The downside is that they do allow the aeg to be used once they have cooled down so if the problem has not been addressed, further damage may be caused.
Intrinsically self-protecting circuits are specific circuit layouts found in high end computerised MOSFETs that monitor the power going to the motor and cut it off in the event of failure. They can be thought of as ‘smart’ fuses and are the best possible solution to protecting expensive gearboxes.
Many folks will jump at the opportunity to tell you how long they’ve been running their aeg without a fuse and, unfortunately, so will many techs.
To them I say, cool. I’m glad your aeg hasn’t run into any problems.
But what happens if something does happen?
A fuse is there to prevent the worst happening, much like a seatbelt in a car.
You could drive a car for decades without a single accident and you would be fine.
But if something were to happen, you’d be much worse off.
25. Recommended upgrades on a budget
26. What is shimming and how do you do it
27. What are the different Gear ratios and types
28. Air seal enhancements
30. Flash mags, hi-caps and mid/lo-caps
31. The different types of gas and their advantages/disadvantages. Also an explanation of the naming nomenclature (green, black, red gas etc)
32. Recommended upgrades for gas pistols
33. Barrel length and Cylinder size
34. How do I build a DMR
35. How do I build a RoF beast
36. How do ported piston heads work and why are they necessary
37. Why use different weights of ammo
38. Deans vs Tamiya
39. Part quality list and recommended upgrades for a given budget