Any idea how this happened?

[MasterGouken]

Right, i have a new G&P SR-15 and i took it to Phoenix Airsoft on saturday. The only upgrades were a madbull tight bore and a madbull red hop rubber. When it was chrono'd it was firing around the 485 FPS mark! Needless to say i had to hire as i couldn'd use it.
The next day i went with a mate to a site in Kettering. When we got there i told them my aeg was too hot but they decided to chrono it anyway. Weirdly it was only firing between 335-352 FPS!

Surely different site's chrono's dont have that big a varience but how can an aeg lose over 100 fps overnight? This leaves me unsure as to whether or not i should change the spring to an m100 as, if its only now firing at around 340 average, i don't need too. But then, if it's chrono'd again at Phoenix (my local site) and its around 485 again i can't use it!

[happyal]

Re: Any idea how this happened?

Sounds like a dodgy chrono reading. If you have a chrono, or know someone with one get some reading on your own.

Some chrono's are very light sensative.

[danhc]

Re: Any idea how this happened?

where you using the same ammo and possibly an air seal issue?

[MasterGouken]

Re: Any idea how this happened?

I used the exact same ammo (.20 Blaster BB's) and the same battery. The light conditions were similar, weather a little bit different (was raining lightly on and off at the Kettering site and just a bit chilly at Phoenix).

Unfortunately i don't know anyone with a chrono so i can't try that

[Fizzy]

Re: Any idea how this happened?

How many shots did Phoenix chrono it with?

[seansamurai1]

Re: Any idea how this happened?

At 485fps on a .20, you would see the round shimmy from side to side as it flies, used to get it when chronoing my sniper rifle!

[MasterGouken]

Re: Any idea how this happened?

Phoenix chrono'd it with 5-6 shots. Close Action chrono'd it with 5 shots. I was the one firing it both times and saw the readings for myself.
Yesterday at Close Action the BB's were mostly flying straight, no side to side movement but the odd BB would curve off to the side of where i was aiming when using full auto.

[No1_sonuk]

Re: Any idea how this happened?

Were the chronos the same make? I have seen a 10 fps difference between Xcortech and Madbull chronos, but not 100.

[MasterGouken]

Re: Any idea how this happened?

I'm not sure if they were the same make but they looked the same to me. I highly doubt that chrono's could have that much of a fps difference anyway, i think it must be the aeg itself.
Could it be that it is hot but an airseal leak is dropping the fps by that much?

[MasterGouken]

Re: Any idea how this happened?

Just ordered an M100 spring, i'll fit that and see how it goes. Anyone around Nottingham got a chrono i could test it with?

[JOE90]

Re: Any idea how this happened?

Give steveuknotts a pm about the chrono, he may be able to help you

[MasterGouken]

Re: Any idea how this happened?

Oh cheers mate will do