[Hectic]

well depending on air seal barrel length and cylender volume matching a 130 or 140 spring will get u into the 450fps range. Ive never looked inside a g&g but youll almost definately want to change the piston at that lvl of spring, put a good piston head in for beter compression, shave the seccond tooth off the piston, maybe some of the third one too and add a sorbo pad to correct the aoe. Shim everything well add a fet to eliminate the trigger contacts then run an 11.1 lipo. Thatll help yer trigger response with a heavy spring (also not sure about the g&g motor. Then youll want a good inner barrel and a good hop up rubber and bucking (i use the prometheus smooth rubber and bridge tensioner but the modify flat and rhop are good at lifting heavy bbs too) then run some .30 or heavier bbs thatll give u some good range and accuracy