[lurkingknight]

there's a couple concerns for a stock aeg... especially when running 11.1 lipo

Whether you run a 90 or 150 spring, there's a few things that are likely to happen.

arcing at the trigger contacts this occurs regardless of what batteries you use.. but higher voltage and amperage will accelerate wear on these parts... eventually you'll burn right through them and they'll fall apart and you cant close the circuit when you pull the trigger... results in no fire. a simple mosfet wired in can fix that for you... it's a relay essentially, sending minimal voltage through the trigger contacts to trigger the firing and it bypasses the current going through the switch.

Shooting a gun only in semi actually increases the wear, because the block that closes the circuit in a semi mode shot is pushed into the gate and reset every time you pull the trigger. There's a little arm that gets moved by a cam on one of the gears that flip the trigger block back to reset it onto the physical trigger. You also voltage spike the motor as it always requires more energy to start something moving from a complete stop. In full auto, that little reset arm called the cutoff lever gets pulled out of the way and the block remains pushed into the gate until you release the trigger. The cutoff lever also wears as long as you are in semi mode, since it's always being ground by the cam on the sector gear, this is a wear and tear part.. the more you use semi, the faster it wears.


the stock piston in vfcs is a clear plastic one... it has a lifespan of 1-thousands of rounds. I've heard of them blowing up on the first shot with weaker springs. It's definitely an immediate weakpoint.

After that it's anyone's guess how long it has. The gears are generally the next fail point. You'll lose a tooth or something will shear. On VFCs I think it's the spur gear or the sector gear that gives out.

When some of us talk about AoE we're talking about the angle in which the first tooth of the sector gear (the one that draws the piston back) meets the pickup tooth on the piston (the tooth with the widest face at the back of the piston. Part of the AoE treatment with sorbo is that it pushes the piston back (a measured thickness) so that the tooth on the gear meets flush with the tooth on the piston, distributing the load across the face. Some setups from factory have it not bad to start others will drive an edge of a tooth into the pickup.. this can lead to shearing the back of the piston off.

The other part of the AoE correction is that by moving the piston back, you change the length of the stroke, slightly shorter, so when your gears are moving really fast from a high power motor or battery, that they will always pick up the pick up tooth, and not in the middle of the shooting portion of the cycle when the piston comes forward.

On some setups it's very possible for that sector gear to come for a 2nd cycle before the piston finishes the 1st. Be it from a compression jam that delayed the piston from coming forward or just really fast gears. That's called premature engagement and it usually destroys the rack on the piston requiring a replacement.

PmE can also happen on a smaller scale, sometimes you take a piston out and you see the marks on the 2-4th teeth where those teeth are starting to wear down from the sector gear having a weird mesh when they meet.

Installing sorbo has a 3rd effect of being soft and absorbent enough of shock from the kinetic energy of the piston assembly slamming into the front of the gearbox. It's been proven to help prevent the front of the gearbox from cracking off. Sometimes gearboxes will crack in cold weather... other times from excessive shock from repeated cycles.