Guys. Thanks for all of the suggestions. Now I am clear. I will post pics of the finished gun next week.

Thanks for the suggestions guys. Exactly what I needed. I want to tap as few holes as possible. I will go ahead and tap.

Yes - all PVC - schedule 40 with a 1" modified sprinkler valve

I am trying to find a piece like what these Systm guys used on their bigger pneumatic cannon that basically has ...

Building my first pneumatic and want to make sure i do the right things here. From searching ,i know i need to tap at double wall joints. Do i simply self thread them in after drilling and then coat on both sides with silicon or epoxy. I just want to make sure i don't blow one of these out.

Thanks