AK-47 Downgrade Spring

[Jamroxorz]

So I have an Echo 1 Redstar Ak 47 wood, and everywhere I look at reviews and websites it says it shoots around 420-450 FPS stock. I haven't actually chronied it yet cause don't have access, but I'm assuming it shoots over 400. So I went to a store and asked what spring would provide around 350 FPS cause I notice for most games that's what the hosts cap the FPS at. so the guy told me to get a M100 spring, so I got it. First question is; is this the right spring for the job? Secondly I asked if he could install it for me and he said he charges 40$. I declined for now, I wanna see what you guys think the price should be, that's if I cant do it myself. Are there any guides or easy steps to changing the spring?

Thanks a lot =]

[HKGhost]

Use youtube to help with disassembly and Mechbox.com. For 350 fps, you should be using m90 (330 fps) spring and a tightbore. That should get you close to 350 but still staying under. M100 should be around 360-370 depending how good your airseal is and what barrel you have. A longer barrel will increase the fps a bit so does a tighter barrel. Get access to a chrono to confirm.

[THEMAKKER13]

Yeah use mechbox and youtube. I think you should be fine with an M100, but with a tightbore it would be close. My G&G M4 had an M100 and no tightbore and was at 340.

[Jamroxorz]

I have a hop-up unit too, doesn't that shave off some fps

[Slow]

Thing to decrease FPS...
Change Spring
Change Hopup rubber

[Jamroxorz]

Yeah I know FPS doesn't matter too much, but I need to change it so I can play =]

[THEMAKKER13]

Slow, what are you talking about? Compression is a part of your fps, if you have an air leak, your fps will go down, if you have a good seal you'll have a nice fps. Yeah the friction of the rubber causes the bb to slow down, but I don't know if changing the rubbber will decrease it that much. The main thing you want to do is lower your spring. That will keep your gearbox alive longer and raise your rate of fire.

[Jamroxorz]

Is it hard/dangerous( for the gun) to change the spring myself when I'm a newbie?

[Slow]

No, just make sure to watch some videos on mechbox.

[Jamroxorz]

Alrighties thanks guys

[pestobanana]

The original designation for the number on the spring was metres per second. So M100 is supposed to be 100m/s or 328 fps. However a better air seal does dramatically increase performance. I got 420 before with an M110, which is only supposed to shoot 360 ish.

Changing a spring is fairly easy. Anyone with basic technical skills can do it.

[Jamroxorz]

Ya, I think I should be able to do it. I'll try it tomorrow =]

[Jamroxorz]

Hey! So I did it! I managed to actually change the spring so now it's field ready =D. There's was one annoying part, the reverse lock thing, it was a pain. But ya, now I know how a mechbox works exactly. Well thanks a lot everyone!! =]