ICS spring upgrade 303FPS - 345ish

[flakjack]

Hi guys,

Had a quick butchers through the forum and haven't found the perfect answer.

I've got a stock ICS M4 i've had for a few years and have recently been getting back into airsoft. I'm looking for a simple spring upgrade to bring the FPS up from 303FPS to something a bit closer to the site limit (345FPS).

Looking at guarder M90/M100 springs and was wondering if anyone had an idea of which one is likely to give the best results.

I've been considering other upgrades but the stock internals and air-seal are in pretty good nick and ICS parts tend to be pretty sturdy.

Any ideas?

[badger906]

Re: ICS spring upgrade 303FPS - 345ish

an m100 spring is rated at 100m/s so will give a fps of around 328.
an M110 will give around 360fps~

[Genesius]

Re: ICS spring upgrade 303FPS - 345ish

i always thought an ICS shot hotter than that at standard? i stand to be corrected though. just thought id mention it as my ics shoots 360-375 and its got the original spring that screws into the piston.

[badger906]

Re: ICS spring upgrade 303FPS - 345ish

My ICS m16 shot at 314fps out of the box, got a call from my local shop day after i ordered it asking if i wanted it upgrading, but im happy as long as my guns shoot over 300fps

[flakjack]

Re: ICS spring upgrade 303FPS - 345ish

Cheers guys, might give the M100 a go then

[sj_asc]

Re: ICS spring upgrade 303FPS - 345ish

For efficiency sake, if you sort the seals out, you will not need such a high rate spring.
Doesn't necessarily mean throw all the old parts in the bin and buy new, yours may alredaly be better than many aftermarket parts anyway. Basic compression check, without the airseal nozzle, if thats fine try it with the nozzle (extended too). If thats fine, all is good. If not, buy one with an o-ring that seals between it's self and the cylinder head nozzle - Guarder, SHS, Modfiy, Systema or Prometheus are good.

Bigger air leaks - Between the airseal nozzle and hop bucking lip.
A good hop bucking with thicker lip will help, Marui, Systema, Guarder etc are all great.

For reference, i've hit in the 340's with Guarder SP90's and in the same setup the SP100 hit into the 390's though in a reasonably well sealed setup the SP90 will settle around 330 fps w/.20g. and the SP100 never seen below 370fps in a stock marui gun.

[julesbloke]

Recently put Guarder M90 in two of my ICS m4s and both shoot around 300 give or take. I'm trying to hit 340ish (I know it doesn't make too much difference - personal preference) so I've ordered Guarder M100 and M110 springs. When I get them I'll chrono once they're installed!

[sparrowhawk]

Re: ICS spring upgrade 303FPS - 345ish

two days ago i put a guarder sp100 into an ics split gearbox it fired around 280 fps without the screw in the rear of the gearbox that goes through the spring guide, put the screw in and it shot up to 335-340

[julesbloke]

That's interesting. Some of my uppers have the screw and some don't.

Going to have to experiment now!