SpudFiles

mostly relating to safety:

i have heard of the safe pressure level for pvc being 100-150psi regardless of vendor-stated rating; is there an effective formula to determine the actual safe levels for piping of a given id, thickness, construction and material?

is it safe or worthwhile to make a "double reservoir", where a large reservoir would connect to a smaller one via one valve, and the smaller one would feed directly feed into the barrel, but with a second valve separating the barrel from the smaller reservoir (allowing one to effectively split pressure off of the larger reservoir and *possibly* allowing for multiple useful shots off of one charge?) thank you!

Look up Geo Schoonmaker on youtube, he has an airgun that uses a large air chamber that feeds into a smaller one via ball valve for better air efficiency, it allows him to get a few shots off a single charge, although the shots will drop in power.