I agree with Airgun Gear I recently watched a Myth Busters episode on dry ice in (wondering if I should even tell the process, it's aired on tv) a plastic soda bottle, water and caped, they measured it at (get this) 7psi before it failed and highspeed video shows it bending the 1/4 inch thick steel bracket that holds the bottle!
I question the accuracy of the psi because they measured from outside the bottle rather than being tapped into it. >shrudge< regardless of actual PSI it was a PET pop bottle rupturing and it bent 1/4 inch steel.
here's the video
https://is.nisd.us/apps/video/watch.jsp?v=65412
it is at 43:00 where it starts to get interesting and through 47:00 showing simulated hand damage.
also, web search shows PET bottles rupturing at a varying psi of up to over 200psi validating my skepticism of 7 psi.
But were talking in the 3000psi and higher with PCP Airguns. Pressures this high must be handled with extreme caution. Improper handling can cause severe damage to persons and property, possibly even death.
Be Safe