Looking to build a V2 Gearbox from scratch.

Discussion in 'Gun Building, Modifications & Repairs' started by SeanG, Sep 2, 2012.

  1. SeanG

    SeanG New Member

    Let me start off by saying that I'm not here looking for anyone to do all the work for me, or hold my hand and walk me through everything step by step. I'm mainly looking for quality & budget savings.

    Ok so I've been toying around with a custom V2 gearbox for my M4, I want to build one from scratch, and would like the community's opinion on what I have so far and let me know if I've missed anything. Let me know what you think (I know there are cheaper/better quality options out there, just don't know what they are or where to find them).

    This was the first list I put together, just running from what I could recall I would need and trying to find parts that fit the bill on ASGI.

    • Systema Reinforced 7mm Gearbox for M4/M16 Series (really thinking that I should go with an 8mm box but not sure which to get)
    • Modify Modular High Speed Gear Set for V2/V3 7mm Gearbox (not looking for outrageous ROF or high FPS, somewhere around 350fps and 20+ ROF would be fine)
    • Madbull M100 Spring
    • Systema Ver2 Metal Spring Guide
    • Action Army High Speed POM Reinforced Piston w/ Metal Teeth (14)
    • Bravo Aluminum Piston Head w/ Thrust Bearings
    • Magic Box Ultra Efficient Teflon Coated Aluminum Cylinder for M4
    • Modify V2/V3 Stainless Steel Cylinder Head
    • Prometheus Air Nozzle for M4/M16::
    • Modify Anti-Reversal Latch for Ver2&3::
    • Rewire from front to back using:
    • Systema Low Resistance Wire set for Type 2 Gearbox
    • Add Deans Connectors to both gun and battery
    • Definately adding a MOSFET (but not sure where the best place to get on would be)

    • Last I will be powering all of this with a G&P M120 Ultra High Speed Motor (Long Type) and either a 9.6v or 10.8v NiMH or a 11.1v LiPO (all depending on what would work the best for the ranges I'm aiming for: 350ish FPS & 20+ ROF)

    Thoughts? Comments? Anything I missed?

    This is a second run of a Custom V2 Gearbox from scratch after toying around on Clandestineairsoft (recommended to me by several people)

    • Lonex V2 Gearbox Shell w/ 8mm Bearings, Tappet Plate & Selector Plate
    • SHS M4 Safety Latch (cover)
    • Steel Version 2 Cuttoff Lever w/ Spring and Screw
    • SHS V2 Trigger Contacts & Assembly
    • 13:1 Ultra High Speed SHS Gear Set w/ Gen 1 Bevel
    • SHS Shims - 27 Pack
    • SHS Anti-Reversal Latch
    • SHS Sector Gear Delayer Chip
    • Lonex Plastic POM Ball Bearing Piston Head
    • Scatterplot Sorbo for V2/V3 Gearboxes - 1/8" Thick - 40 Duro
    • M4 Cylinder Head
    • SHS T3/4 Type II Cylinder
    • SHS Nylon Piston w/ 15 Teeth "SHS Blue 15 Tooth"
    • Aluminum M4 O-Ring Nozzle
    • SHS M100 Spring
    • Super Shooter Stainless Steel Ball Bearing Spring Guide for V2
    • SHS High Torque Motor - Long
    • Speed Airsoft M4/M16 Tuneable Trigger (Black)
    • MOSFET definately

    My third option would be buying a JG / CYMA Enhanced 8mm Gearbox for M4, instead of going from scratch. IF I was to go that route what all parts on this list could I cut out in order to improve the JG box from Evike?

    Thanks for any and all help.
  2. alex

    alex New Member

    cheaper alternative:

    used JG 6mm gearbox with stock internals: $10-15
    replace wiring with 16awg, mosfet and deans (i have a spool of 100 feet, $80 for the good stuff, but you can find it cheaper). home made mosfets can be built for around $5, dean clones 10 pairs for around $6 i think.
    replace piston o-ring with #14 o-ring from home depot (package of 10 for ~$3.00 i think)
    clean, re-shim, re-lube and adjust AOE (don't forget to radius the gearbox).
    madbull blue bucking, 2 pairs for $10-12
    i've switched over to deepfire o-ring nozzles (looser fit than shs nozzle for better rps). can't remember the price
    stock spring on a used JG should be around 380 fps but they usually break and goes down to around 350 fps.
    you can replace the 6mm bushings with 6mm bearings for a little more rps and longevity.

    i have a few of these as spare drop-ins.

    any neodymium magnet torque motor will work fine. element motors are around $25-30 shipped.
    7.4v 35c 2200mAH is around 18-20rps
    11.1v 25c 1600mAH is around 28-30rps

    this is a cheap build that i've been using for over a year and works great.
    if you go 11.1v, i recommend replacing the piston with an SHS 14 or 15 teeth and using any non metal piston head (i prefer guarder, $10).

    you can replace the sector gear with a riotsc dual sector gear, drop in a guarder sp150 and double your rate of fire at around 330-340 fps (~50 rps with 11.1v or ~35 rps with 7.4v).
    Last edited: Sep 2, 2012

  3. Gaz96

    Gaz96 New Member

    I've heard bad things about G&P motors, I'd get yourself an SHS High.Speed motor, don't really need a high torque one for 350 fps builds, however, if you buy a high torque motor, it's likely to last longer
  4. CoppertopNeasg

    CoppertopNeasg New Member

    I would go with a SHS, Lonex, or Amp High Tourque. Putting a high speed motor in this particular set up will be inefficient and consume a lot of mah.
  5. SeanG

    SeanG New Member

    Talked to Ben over at Clandestine and he told me that he will be getting some of the parts I'm looking for in either today or later this week! As far as the motor, what surfer said is why I went with the SHS high torque motor, instead of any "high speed" or "balanced" motor.
  6. Lefse

    Lefse Well-Known Member Supporting Member

    You definitely need a stronger spring. You're begging for pre-engagement with an M100 spring, use at least an M110 or higher. The SHS high torque will easily pull this setup, but you'll need a strong battery, don't bother with a ni-mh, a good 7.4v li-po should put you close to 30 rps with 13:1 gears. You should get around 20 rps with the SHS high torque and 18:1 gears with a 7.4v li-po.
  7. SeanG

    SeanG New Member

    Anyone ever heard of
    From what I've gathered you can earn points by doing surveys (or buying stuff if that's how you prefer it) and with those points you can buy ANYTHING you want that's listed for sale on Amazon.? Right now I'm working towards a JG v2 gearbox they have listed on there, to use as a base for this build I'm working on.

    If any of you have heard of it before or know anything about that site let me know.