« on: February 27, 2012, 09:35:35 AM »
Here in the Dominican Republic, Airsoft is a small sport with only one hundred or so active participants. Naturally, professional airsoft gunsmiths are non-existent, but we do have a few 'practitioners'. On my team we have an electrical engineer who has helped us with various AEG and spring sniper repairs/mods/builds and he has learned a lot and done well with few mistakes resulting in broken parts.
His most recent scout/sniper project (for me) is taking a stock G&G Combat Machine M4 and installing a Guarder 150 Infinite Torque kit and Systema A to Z motor.
Once everything was assembled, we shot the first .20g bb through the Chrono and it was 500+ fps. The following shots dropped to 400's, 300's, 200's, and then we looked at each other in bewilderment. We opened the gearbox and... drum roll... half the piston's teeth were gone... (we had filed off the second tooth before installation as so many 'experts' recommend)
We pulled out a bother brand new Guarder half-teeth piston (same one that comes with the kit) and changed the motor back to the stock one. The result isn't much better...
Thought process: all the upgrade parts are top-notch, the piston and the gear that works it are making good contact... so is it the G&G gearbox that is causing this?
Any advice and verbal abuse is welcome...