Spring downgrade for ptw
 

Sorry for my noob question but I have gotten some mixed information. I bought a used 2008 ptw with a red cylinder. I am wanting to downgrade the cylinder to 400fps. I have heard that all cylinders after 2006 have interchangeable parts, but the red cylinders have no porting compared to the other colours. I have also read that people are switching an m110 to their red cylinders to get 365fps. So will this work dropping in the m110?

Check your cylinder. Does it have a hole opposite the rack gear? If yes, then it's ported. Either way, grab an PTW M110 spring and switch it for the M150 that comes with red. That should drop your FPS to below 400.

Or get a VSR-10 spring (around SP120) and cut coils until you are 410. Then heat the cut end red and press on a metal surface (not thin, something thick).

If you have a stock or PDI barrel that's 14.5" or SHORTER, you need a ported cylinder to get the best use of your spring.

If you have a barrel that's longer than 14.5" or is an ORGA 6.13 in specifically a 14.5" length, you need an unported cylinder.

If you have a stock barrel, M110 spring in a ported cylinder should do 380fps easily.
If you want to bump it closer to 400, you can get an ACM spring guide collar kit for PTWs, which are shims you stack on your spring guide to bump up fps a bit.
Being used, you'll want to regrease the cylinder, but you can't use the same grease you use on AEGs (it's crap), you have to use systema cylinder grease of tamiya ceramic grease.

RSOV will have both vanaras springs (same rating-fps as systema springs) and ACM spring guide collar kits

I'm using a Systema blue cylinder, with a Systema blue spring (M110) and a shim (green?). It shoots about 395 FPS.

Hey thundercactus, just so I know a little more about the system. When you say to get the most out of the cylinder I’m guessing that your meaning that the porting helps get the allow the correct amount of air to be pushed out of the cylinder to propel the bb out of the barrel but not too much that a lot of air is pushed out after the bb leaves the barrel. So if the red cylinder is rated at 500 fps and is sent out with these short barreled guns this over volumed problem should be even worse at 500 fps with even more air wasted and piston impact. What I am getting at is there anything detrimental with running an overvolumed ptw?

Not detrimental mechanically, but you might have an fps drop due to overvolume.
So you might be shooting 350-360fps instead of 380-390fps on the M110 spring.

Thanks for the help! I have been looking for replacement cylinders. Most places sell king arms or velocity cylinders. Are these the same quality as the systema cylinders?

Either trade cylinders (or cylinder shells) with someone (some people do need the unported cylinder for running a 14.5" orga barrel) or just get a ported king arms or alpha arms cylinder.
$150 for a systema stainless shell is outrageous.
If you plan on using the alpha or king arms internals though, its a really good idea to take the cylinders apart, regrease, and reassemble with blue loctite.
The KA cylinders are notorious for falling apart while shooting if you dont loctite them.

Alright, thanks for the help!

What is the difference between king arms/alpha arms and systema branded aluminum cylinders? Other than the locktight are you paying for a name or is there a performance difference are ptw cylinders just a name?

Parts quality is substantially better on Systema cylnders. They have not made the aluminum ones since 2011. The early stainless versions had so e fatal flaws in them.

mcguyver when you say fatal flaws, do you mean in its design or qc issues?

QC I would say. There is a thread on ASC where I explain in detail how to determine if you have one of the flawed cylinders, as well as a prototype I built from one to "resurrect" it if you will.

Jezz I just read the information in the doctor's corner! From what I gather about cylinders so far,
Off brand aluminum - lower quality
systema aluminum -dents relatively easily and if bought today are at least 5 years old
systema stainless - may have too much play in piston
Fcc/velocity - stainless quality isnt there

At the prices that stainless cylinders are I was hoping to grab something second hand. And seeing how people dont always tell the truth about the age of parts, is there any cylinders that you would recommend? Tokyo Arms Steel Cylinder and throw in my systema piston?