I find a lot of people who have in depth knowledge of pcp on this forum.Valve spring has been previously discussed many times on this forum.I just want to share my personal experience and want to know the technical causes behind it.I have RAW HM1000X high power.I do tinkering myself. I made some new parts and let the stem of valve open in atmosphere. This allowed me to decrease the hammer weight from more than 70 gram to 32 grams.I had to put a lighter hammer spring too.Now I was achieving the powers of my OEM RAW set up but the extreme spread was too much.After a lot of trial and error when I installed a very strong valve return spring my extreme spread came into single digit instantly. So I see the the valve spring tension in regulated pcp has a lot of effect on the consistency of the gun.I understand that as in the modified set up the valve opens easily, it needs much more strength of valve spring to act in harmony with the new modified parts.Please discuss this matter. Regards, Umair Bhaur
Absolutely, a stronger valve spring flattens the curve in an unregulated PCP, allowing a wider range of pressure between fill and refill, and therefore more shots.... The downside is the hammer strike must be increased to get back to the same FPE....The decrease in ES I have heard reported is in a regulated, benchrest PCP....Bob
Even with the @@ss%% spring mod .. If the vent hole in chamber BECOMES TOO SMALL the dwell is chopped so successfully power takes a major dive !!!Takes rifles such as the old BAM 50 ..... MASSIVE poppet spring !!!!!!!!! and equally HEAVY hammer to counter it. Any lighter of hammer while the OEM poppet spring is in place and gun is a total dud.
Not sure I understand your question.... Do you mean comparing regulated to unregulated?.... Balance valve to conventional?.... Bob
Probably not, it depends on the balance ratio of the valve, and how much the hammer spring was reduced.... However, fitting a really strong spring inside a balanced valve may be a challenge, due to the size of the balance chamber....Bob