Question about pressure in firing chamber

[vng21092]

I just saw this post http://www.spudfiles.com/pneumatic-cann ... 24091.html and since it was posted a while ago, I'm not sure if OP is still around to answer my question. When the chamber/stock is pressurized and the slide valve is opened, how much pressure actually goes into that little firing chamber in the QEV? I mean I might be interpreting this wrong but he says he pumped it to 150psi, so when the slide valve opens wouldn't the pressure in the firing chamber raise by just a tiny amount?

[jackssmirkingrevenge]

Maybe you're not getting how it works, here's a pretty exhaustive explanation: http://www.spudfiles.com/pneumatic-cann ... ev#p365630

[vng21092]

yup, I thought how that works, my question was how much pressure is in the firing chamber after it's charged, since the firing chamber is so small?

[zeff]

Pretty simple stuff, the pressure will equalize on both sides. If the hole is small it might just take a bit longer.