Do Tight-Bores Increase AEG Velocity?

Do “Tight-Bores” increase airsoft gun velocity?  I have been reading this question over and over again in our FRAG forums. Well here is an article from Redwolf Airsoft which they tested and compared the basic or “stock” inner barrels with the high ends. Check it out.

How to use ICS Forward Assist Function the Right Way.

I have noticed that there are a good number of ICS M4’s users lately. But many of us still doesn’t know when or how to use this useful function the right way. I am going to post important and helpful tips about the Forward Assist Function which ICS published in there website. The full context of this of this topic can be view here.

ICS Forward Assist Button

1. Although AEGs is a toy gun, we still apply the norm of real gun on airsoft gun. We have to unload airsoft gun first after shooting or combat.
2. When we don’t use the airsoft gun, we have to release the magazine and change fire mode to semi-auto. Point the gun toward safety area and clean the pellets remaining in barrel by shooting two ~ three times. Then push the forward assist knob to release piston and spring.
3. Pushing the forward assist knob when the fire mode is still in auto may cause the broken piston. As it mention above that there are four possible stop points of the piston after automatic shooting. If the piston happens to be at the forth position and players push the forward assist knob, No.3 gear will reverse too fast because of the inertia and rebound which result from the tension of spring. The reversing No.3 gear will hit the last teeth of piston and may break it. This situation gets worse with more powerful spring setting.
4. The proper way to use forward assist are first, release the magazine, Second, Point the gun toward safety shooting area and clean the pellets remaining in barrel by shooting two ~ three times. Finally push the forward assist knob to release piston and disassembly battery plug. Then store your airsoft gun into carrying bag. Forward assist knob is not for using at any moment. The proper timing of using forward assist knob is after shooting or combat and all the unloaded processes are done.

For more info about ICS Foward Assist, please click here.

ICS M4A1 Main and Gearbox Assemble/Disassemble

A video guide for ICS M4 users. 🙂

ICS M4 Main Disassemble.

ICS M4 Main Assemble

ICS M4 Gearbox Disassemble.

ICS M4 Gearbox Assemble

Prepare for the REVOLUTION!!

UPDATED!! Buckle your seatbelt, as the Revolution is going to hit hard. SYSTEMA is proud to announce new development of a revolutionary gearbox system (for Version 2 guns) that will bring AEG performance level to new heights. Be prepared to experience the SYSTEMA Revolution!




State-of-the-Art Technology — The SYSTEMA Revolution represents the pinnacle of AEG gearbox development while maintaining 100% Ver.2 compatiblity!

» Guaranteed 100% backward-compatible with Tokyo Marui (TM) AEG bodies.
» Direct drop-in replacement for many other AEGs that complies with the TM Version-2 Mecha Box Specification.
»Advanced fire-control electronics and power-regulating MOSFET circuits.
» New loading mechanism /nozzle design.
» Hand-tuned high-output motor precisely matching the new gearbox’s gear ratio.
» Extremely tight manufacturing tolerance ensures superior performance, shot after shot.

Advanced Firing Control— The SYSTEMA E.C.U. (Electronic Control Unit) is a direct decendentof the PTW’s fire control unit, specifically tuned for the Revolution:

»Factory pre-programmed electronic triggersystem.
»Optical sensor array constantly monitors gearbox operation, precisely applying power (and braking) to the motor so that the gearbox will always cycle completely at every trigger pull. This new function entirely eliminates the need for anti-reversal latch.
»Using optical sensor to precisely determine the position/rotations of the gears, the Revolution is also capable of providing the world’s most reliable 3-shot burst operation. No more fiddling with inconsistent “timer based” burst mechanism!
» MOSFET regulated power delivery circuit ensures stable and consistent performance.

Performance and Reliability — Innovation is only half the story. The SYSTEMA Revolution will also far exceed the current standard in terms of performance and reliability:

»New nozzle design eliminates breakage-prone (and decade-old) tappet plates.
»High-strength, all steel gear set ensures reliable operation year after year.
»Full-length steel rack gear greatly extends piston life.
»Top quality components used throughout.
»Factory-backed U.S. warranty when installed by a certified SYSTEMA Gunsmith.

Click for Revolution FAQ


Full Teeth and Half-Teeth Pistons plus Helical Gears

My “Happy Gun” (my guinea-pig M4A1 Rifle ) went again to the operating table today. As Myself, Bobby, Kurt and the “Man of Steel” went through the process of cleaning and upgrading the rifle’s gearbox, we came to a point where we discussed the difference between a “full-teeth” and “half-teeth” piston. What exactly is the point of a half teeth or full teeth piston? I don’t really see the point of them. What about the Helical and Standard gears? What’s the difference?


Helical Gears

Increased load-carrying capacity (compared to normal straight tooth gears) due to several sets of teeth meshing simultaneously.
Smoother, quieter operation due to less backlash related to several sets of teeth meshing simultaneously.

Helical Gears experience axial thrust (I.e., gears push themselves apart axially), this can be minimized by using metal bushings (not bearings).

Helical gears are more expensive, but given the pros are worth it.

Helical gears are weaker in terms of taking abuse but runs much quieter. This has been the same reason in automotive transmissions for years, in the road cars you find helical gears are used to reduce gear noise while on race cars where the box is often abused and have to pull heavy loads they use standard type of gears as they hold up much more to the stress.

Full-Teeth versus Half-Teeth Pistons

Full-Teeth pistons are utilized for gearsets under an Infinite Torque-Up set as the sector gear driven teeth are smaller in diameter than the piston pinion teeth.


Half-Teeth pistons are utilized for Infinite Torque-up sets as the sector gear driven teeth are the nearly the same size or the same size as the sector gear pinion teeth (I.e., the sector gear pinion teeth are as half-as wide as a normal sector gear).


Shimming the Gears

I have been experimenting on different “shim” setups for the past couple of days. Though I made good progress in making the gears work, I wasted 5 or more gears in the process. Thanks to my FRAG buddies, Bobby and Rael for their assistance in closing the damn gearbox and greasing.


Shimming your gearbox is one of the most important things you can do to when working on your aeg gearbox. Proper shimming allows for easy movement of the gears while at the same time reducing the amount of bounce that your gears experience.

Overshimming your gearbox will cause excessive friction and drag on your motor and battery. Undershimming your gears can cause a bouncing action in the engagement of your gears causing excessive wear on your gears and bushings.

This is only a starting point for the proper shimming of your gearbox. Each gear may require more or less shimming. If excessive shimming is needed you may have a deformed gearbox shell.

Below is a diagram from Arnies Airsoft about the different shims sizes you will be using to make your aeg gears work properly.


Tiny things that are rather important…

AEG Springs (Comparison Chart)

This airsoft spring guide is better used as a reference guide to compare relative performance between spring types and manufacturer than an ACTUAL speed/performance chart. The peformance numbers in this article are based on data compiled by Brian at


Less than 400 FPS Chart

This chart illustrates the springs made by a variety of manufacturers that typically produce velocities below 350 feet per second.


Upgrading the mechbox with springs that create between 350 FPS and 400 FPS will increase stresses on most AEG stock components. In most cases it is not required to upgrade more than the bushings. It is still a good idea to reshim your gears while adding bushings or confirm you have metal bushings.

Suggested improvements

  • Reinforced gears (especially for Tokyo Marui owners)
  • Metal bushings

Over 400 FPS Chart

This chart illustrates the springs made by a variety of manufacturers that typically produce velocities over 400 feet per second.


Upgrading the mechbox with springs that create more than 400 feet per second results can create very high pressures and stresses on most AEG stock components. It’s highly recommended that the following items also be upgraded when considering an upgraded spring at this level.

Recommended improvements

  • Reinforced gearbox (the actual metal case)
  • Reinforced gears (especially for Tokyo Marui owners)
  • Metal bushings
  • Torque Up gears (recommended)
  • Higher mAh and/or voltage battery


It’s worth noting that any time you are upgrading AEGs to these levels, you significantly increase the chances for future failures and reduced reliability. AEGs can be upgraded to levels beyond 400 FPS with reliability, but great care and expense often comes along with upgrades in the territory of 450 FPS or higher.

Article based from