Good head? the outcome of an obseervation

so, building the retro arms split with a m115 - coming along nicely but some hiccups like destroying the piston.

anyway, bought a cylinder locally (pic to follow) but its had a crappy piston head on it so figured…put on my one (black one) from gba that was spec’d with the build (red one)

as i inspect the red one which has cycled maybe 3 mags through the blaster i noticed a fair amount of wear

after giving the pickle some thought because wear isn’t something i want to see in this build, i came up with the following which is butchered together from one of those absolute stock piston heads that you screw through from the top into the piston with no bearings etm.

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anyone done this? what was the outcome?

The wear on your piston head is interesting. Looks like there is a lot of play in the cylinder piston as it moves.
I’m thinking that the rails that the piston runs on are not making enough contact with the piston.
Either too sloppy or the spring is too stiff and forcing the piston in at an angle.

If so, a fix could be a longer piston head (longer behind the washer part) so it has more surface area to make it run true?
More guide support for the piston plunger?

I won’t suggest a weaker spring because that’s just crazy haha

Any head I can get is good head… I never complain (unless too much wear too soon)

The worst thing is being sprung in the middle of it. Can be hard to swallow!

Did you use lube? That can cause wear on head?

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It’s definitely the spring

It’s a 495mm barrel which is why the heavier spring but may have to change it pending it’s fps.

The nylon head can wear all it likes. Won’t damage the cylinder

Does the spring have ‘tidy’ ends so it sits level in the plunger and guide? If a strong spring is ‘crooked’ at the seat, it may make the piston/plunger run crooked too?

Maybe use pliers to make the ends of the spring completely square … especially if the spring has been cut or modified

Ends are good. It’s the spring retainer

The Ra cnc sprint retainer can move :roll_eyes: and it’s been milled specifically to do so…

I have made a washer from a Zac and used an M5 to stop the string retainer from moving

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Head is something that I find has little effect on a build until you start dramatically increasing the cyclic rate then it will make or break you.
Now you can spend a whole lot of time familiarizing yourself with Bernoulli and Coanda or you can look to other high performance pumps such as the combination engine :+1:.
Balancing flow rates to match performance is where it’s at. When you buy a piston head for your blaster then ceremoniously replace the oring that came with it with a nicely colored one, if it’s just a teency bit larger you just changed the flow rate. Now if it’s a well made head from a reputable company then why not trust that they wanted the head to perform at its best and that’s why they supplied an oring with it.
I bet when you were sitting in grade 8 Maths you were looking at the girls or out the window and thinking, I’m never gonna need to use a Pie to work out how big a circle is!!!
A couple of simple equations and you can calculate the areas that the air passes through and if you did that then you will work out how to improve things.

Easy as.

I agree with you to a certain extent but…
Reputable is difficult to ascertain considering for example SHS and FB are both know to be copied and the market is full of copies.
I spoke with FB and they told me that over 95% of the FB sold in Australia is fake :grimacing:
And also the Chinese manufacturing can be hit and miss with quality control.
My company imports from almost every country in the world and I can tell you the Chinese manufacturing on one batch can be extrodinary and complete garbage on the next even after repetitively saying we must have excellent quality control.

The other thing is why do we change the blasters at all instead of trusting the manufacturer who wanted it to perform that way ?
Many things change the flow rate including changing the Spring,Cylinder %, AOE and the Lipo, do you suggest we also leave all that alone too ?

I think good head is a great thing… especially when the seal is good…

Having a ring that is not too loose is also a good thing… I don’t care what color the ring is… as long as it is an acceptable size and there is plenty of lube…

I am not concerned what country the head is from… as long as it suits my nozzle… I very rarely complain although without rubber covering is best… I have heard when the rubber is on the nozzle, it can be a bit hard to swallow? noidea

As we all know, I am sure, bad head ain’t worth spit… puke2dizzy laughing%20(1)

Oh, and I forgot to mention in the post above…

The same can be said for blasters as well :+1: (evidently) :rofl:

Edit: Yes, I am aware I should have quit while I was a head…

Haha Touché,

I see where you’re coming from but I oppose the word reputable, quality and Chinese being used in the same sentence. Unless perhaps anomaly is thrown in too!!
Who am I to talk anyway,
This is the list of box part I don’t modify in my builds:
Spring guide,
Trigger
Shims and bearings
Main spring
The screws that hold the box together,
Anti reverse latch and spring.

I think I’ve got issues

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