What is the best way to clean PCP air rifle barrels?

I started making my own pulls about 10 years ago using string trimmer line (.067") and an old ballpoint pen. Cut the required length off your roll of string trimmer line, cutting one end at an angle. Use a box cutter to cut a 1/8th inch section off the end of a standard ballpoint pen tube (not the fat gel pens). Use a lighter to melt the flat end of the line and quickly flatten that end by pushing it straight down on a hard flat surface. You want a straight, round, flat that is just smaller than the outside diameter of the pen tube you just cut. Put just a tiny dab of "super glue" on the line just below the melted flat, then push the pen tube you just cut, through the line all the way against the flat at the end of the line. Use appropriate size patches for the caliber of the barrel. This size works well with .177 cal. but you need to make larger patches and double them over for .22 cal). Here are a couple of photos.

Mike

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Fishing line with a loop in the middle of it (see fancy diagram above).

The moisture is only an issue if you DON'T shoot the gun and in that case run an oily swab through it for storage.