Well, thats a bit of a mystery... Its supposed to shoot high out of the box (385, higher than the m4)...
I had it chrono'd in colorado at the local shop before i left, they said that was "normal" and alot of their guns chrono low. I second guessed it still and they said alot of guns dont have that high of an fps... I couldn't believe it really, especially since it shoots so far... Is it possible their chrono is just messed up? Should i get another opinion? They just used some random unlabeled bbs, and the first battery they could find that worked... the only thing i can think of is that the motor might need to be adjusted... as it hadnt been since the last reassemble. But i dont know if thats got anything to do with fps... I asked if the battery was fully charged, or on its last legs, and they said that shouldnt matter but that it was, however i dont know that they really knew...
Ive heard of torn hop up bucking causing a decrease in fps, but the stuff i just put in there is brand new (maybe i messed it up, but it looked fine when i installed it). Im pretty sure the piston head isn't loose either as i loctited it in (not with the perm. stuff)... Gear grease was used for the cylinder/piston instead of the normal piston grease as it wasnt around at the time. I know its a bit thicker, but it shouldnt cause an almost 100fps decrease...
im stumped...