Originally Posted by lurkingknight
vfc stock springs can get 400 fps with an upgrade tightbore barrel, what springs are labeled do not correspond to each other from one brand to the next. I'm telling you exactly what springs you need to get under the correct limit.
I just installed the M90 spring as said (I literally had to drive 1.2h to get to a retailer that sells it), what I find peculiar is that the M90 is longer than the stock and is also a bit stiffer? Anyways, putting it back together. Will chrono tomorrow when I get access to one.
Update: While testing the gearbox, I found that the electrical system runs rather hot (wires and battery get warm after 5s of full-auto fire, after 1 minute of testing [3 round burst with 2 second cooldown interval between]) the electrical system was way too hot for my liking. The battery recommended by Mach1Airsoft was [7.4V,1Ah,20C]. I highly suspect it's suffering from high current draw due to the low voltage on the pack.