ICS M4 - FPS Increase

[Priestpel]

Had the first game with my new (second hand) ICS M4. Was chrono tested at around 284fps.... =/
Not bad for a CQB site, but I have a woodland game coming up in acouple months

Just curious how I might increase the FPS; the site max I play at is 330-350....
As far as I know only the spring has been changed on the internals

Cheers

[dave38x]

Re: ICS M4 - FPS Increase

Check the hop rubber - it may be shredded at the back resulting in a crap seal. Also if your comfortable with it then the best thing to do is get your gearbox apart and test the cylinder/cylinder head, piston head and nozzle for any leaks. If you have any, replace o-rings as you need/buy new parts to replace them - if your airseal is good then it may be time for a new spring.

[FlangTal1ty]

Re: ICS M4 - FPS Increase

Most ICS guns shoot very close or over the 350 limit. If the spring has been changed it mright of been downgraded worth a m90 spring. Buy a m100 spring in it and it wail bring it up to speed.

[Priestpel]

Re: ICS M4 - FPS Increase

i believe the spring is a prometheus m110

[No1_sonuk]

Re: ICS M4 - FPS Increase

i believe the spring is a prometheus m110

Then there's something wrong somewhere.
My new CXP runs 330-ish on an M100.

[Priestpel]

Re: ICS M4 - FPS Increase

hmm, doesnt sound good then =/

[mrpugster]

Re: ICS M4 - FPS Increase

It's nothing out of the ordinary, lots of aeg's lose FPS due to worn part's / air leaks etc. There's some simple mods you can do or you may just need some new orings, however you need to be ok with opening the gearbox to diagnose where the fault lies.

If you get the compression just right, i.e. without any leaks, then you can use a lighter spring so less wear on the internals, slightly higher ROF etc. I've had an M110 chrono at 370 before...

[No1_sonuk]

Re: ICS M4 - FPS Increase

My M16 has a spring so light it can barely hold the piston against the cylinder head. That runs at about 330 fps

[Priestpel]

Re: ICS M4 - FPS Increase

I've had some experience with V2 gearbox, but not this ICS one. The guy who had it before me rear wired it as well, so I don't want to yank out cables by mistake

[FlangTal1ty]

Re: ICS M4 - FPS Increase

You problem will only be in the upper gearbox which is very easy to deal with. Buy yourself a new M100 spring and a new o-ring and fit them into the upper gearbox. Im sure you will not have to do any more than this. My ICS M16 shot 370fps with a M100 and a tightbore so yours must be either a spring or compression issue. Open up the upper gearbox and you will find your answer.