That got me thinking about a "bag" that was smaller than an old sleeping bag stuff sack. Along came the fast bottle!
Step 1: Shrinking the "bag"
Then I remembered that lots of people were using the old BPA water bottles for survival kits, dry storage, etc.
I raided the cupboard and found a bike bottle of questionable plastic content (even though I REALLY love riding for the NCMEC every year)!
Step 2: Hole in the top of the bottle
The first time I put the paracord in the bottle the cordage got snagged on a rough edge from removing the inner workings of the lid.
I then went back and smoothed the inside edge with a sharp blade and then a lighter (in hind sight I bet fine sand paper would have been perfect too).