Here's my build, I did the 22' 3/8od copper like the op's. I got a bit of a score though, the guy at the hardware store didn't want to measure out the copper so he gave me what he thought was close enough I ended up with an extra 13' of copper and made a pre-chiller with it w00t
The begining used tape to mark center and end that I cut.
Here is how I rolled it over the paint can.
This is the 2 pieces coiled up pre-interwoven.
Just pull apart and mush together.
Sizing it for my pot.
I got a standard fitting for my faucet that replaces the aerator with a garden hose adapter. Than picked up a female garden hose piece with a barbed end that I had to lube up with soap to get on the 3/8id hose. 6 small ss,and 1 medium clamp later here is the finished product.
I spent about $80 on everything including faucet adapter (go east coast of canada where everything is expensive). A basic 25ft Brewers best IC sells for $89.99 + 15% tax around here. So I saved a little over $20 made a more efficient IC and got a free Pre-Chiller.
Thank you op and everyone else in this thread couldn't have done it without your help, can't wait to give this a go.
Edit: Boiled up a little over 4 gal of water cooled it down to pitching temps in 10 min.