Hello!
I am in the process of making a homemade-ish type of gun out of a drain blaster! For a quick reference to what i'm talking about, please visit this video! ->
In the video, he uses 16mm, 20mm, and 25mm piping (Australian standard electrical conduit , according to him). I was wondering if anyone knows what type of pipe this is, where i can find it, and how tight my darts should be in the inner barrel (elite darts in the 16mm barrel), as I live in the US and am unsure what measurements (1/4 in, 3/8 in, etc) to use