What increases/decreases an AEG's FPS/Joule score

ndf

My son & I each have a JG G36K.

They have been tested on various days when airsofting

On 3 occasions, these AEGs were tested by the airsoft sites and came out with very similar scores.

However, on the next occasion, one had dropped by 20% while the other had increased by 15%. This result was repeated again at the next visit.

Nothing was done to either to alter their condition.

I know that springs can weaken and need to be replaced over time. However, what other changes can cause an AEG to to have a lower FPS? And how on earth does one suddenly become higher?

I know one can lower FPS temporarily by emptying a HiCap magazine on full auto.

Are there care instructions one should follow to maintain the FPS?

thermo

power loss can come from a dried out o ring on the piston head, if you remove the lower receiver complete and spray a little silicone spray oil or similar in through the air nozzle and connect a battery and shoot it on auto this will re lube the o ring. it may take several go's at this. once you are happy with this fire a few shots to make sure no more oil is coming out and re-fit the lower receiver.

thermo

ps how often do you clean the barrels?

T4RGET

[QUOTE=ndf;80629103

I know one can lower FPS temporarily by emptying a HiCap magazine on full auto.
[/QUOTE]

this a myth by the way, A LOT of rounds would be needed to weaken an AEG spring, far more than a person could sit through in one go, mag after mag. anyways, different barrels and hop up set ups can change the energy output of an AEG. Also where you and your son using different brand/ weight of BB's chrono was set up right this wouldn't matter but if the chrono was set to .2's and one of the mags was in fact loaded up with .25's it would give a 'false' reading on the chrono (lower that actually is). just a few things to consider