Pcp experts. Info required.

[Sifu]

Is this a gross generalisation or can the consistency of pcps be improved simply by balancing the hammer spring with the valve spring?

Cheers, Del.

[hareng]

In laymans terms, yes.
Though this would have a very different effect on conventional self regulating knock open valves.
On regulated guns this is where 90% of the problems arise, yet no ones figured or understood it yet. Get it right which means a lot more than a so called blueprint and you will get same power with any pellet hot or freezing cold.

[bengarzy]

Is this a gross generalisation or can the consistency of pcps be improved simply by balancing the hammer spring with the valve spring?

Cheers, Del.

I n real terms the valve spring has little effect on anything as the air pressure, even regulated, puts vast amounts of pressure on the valve (hundreds of pounds in some cases) keeping it on its seat so the spring is there realy only so you can fill the thing from empty.

If the hammer is resting very lightly on the valve stem, the lightest possible valve spring is preferable.

Ben

[99CLOMP]

Is this a gross generalisation or can the consistency of pcps be improved simply by balancing the hammer spring with the valve spring?

Cheers, Del.

sorry I can not comment on your question BUT,,,,,,,,,,
consistency of any gun can be improved by using WEIGHED pellets,, ie pcp in the sweet spot, +/- 7 fps with unweighed pellets,, the same gun with Weighed pellets +/- 3 fps,

[Gwylan]

That's what I thought, but what about the S400 "firing pot?" Does that just set the tension in the valve spring, or does it act as a prechamber as well?

Gus

[spiderman]

That's what I thought, but what about the S400 "firing pot?" Does that just set the tension in the valve spring, or does it act as a prechamber as well?

Gus

Seem to remember someone else asking this question some time ago and not getting an answer.This is something i have also thought about, any answers anyone!

[hareng]

That restricts the flow in standard setup but acts to give the valve its self regulating properties. By this, the spring is under same tension on every rifle which has been worked out in development.
So if valve spring is slackened off or ground down a touch, the power curve will be more pronounced and at a higher peak pressure! Same with any self regulating knock open valve.
On regulated rifles some need or use the extra tension to create more power and same power any pellet! So if a weak return valve spring is slapped in the power is less and higher power with heavy pellets. Now your baffled.
Far easier to slap a weak return valve spring in, set reg pressure and hammer tension, job done 10 mins then worry about temp fluctuations if reg too high.

[spiderman]

Is this a gross generalisation or can the consistency of pcps be improved simply by balancing the hammer spring with the valve spring?

Cheers, Del.

anyone know of any technical books on this subject been written.

[RobF]

Is this a gross generalisation or can the consistency of pcps be improved simply by balancing the hammer spring with the valve spring?

Cheers, Del.

When you mean balancing, what do you mean?

The hammer spring has to accelerate the hammer, which is a lot heavier than the knock open valve, but the valve spring has to absorb the hammer then close against any pressure the spring is still exerting.

Then there's the air pressure effects as well on the valve opening and closing to consider.

I suspect there is something in tuning springs for their consistency that might make guns perform more consistently at different preloads...

[Aeroman]

Getting the hammer weight and spring preload right will affect (improve?) the power curve on a self regulating knock open system, but they would also at a guess need balancing with the transfer port aperture which will also affect any rifle without a second chamber.

[RobF]

I was thinking that even with a reg, it's still down to hammer/knock open valve consistency...