Another DIY approach to patch pull cords begins with grabbing a scrap of string and learning to tie a Perfection Loop (
Perfection (Angler's) Loop | How to tie the Perfection Loop | Fishing Knots). It creates a loop with a very small knot, where the standing end of the cord pulls the loop in a symmetric way. String is easier to practice with the monofilament, just don't pull the practice knot tight, you can untie and repeat.
Then when you are next at Walmart checking for ammo, you can pick up a roll of monofilament (I'm assuming you don't have line in a tackle box for completeness here). Their web site says a 150yd spool of Zebco 50lb test (
Zebco Omniflex Line: Fishing & Marine : Walmart.com) goes for $1.57.
You now have what you need to make a many-year supply of pull cords. If you've never tied monofilament, the trick is to wet the knot before careful tightening.
A loop on both ends where at least one loop is big enough to insert a screwdriver shank, scrap piece of dowel, large nail, etc. gives you a "T-handle" to pull with. Takes a bit of patience to insert through the barrel compared to the weighted end of a Bore Snake, but the price is hard to beat.
I keep a pistol-length and a rifle-length pull cord in my range box, along with some of the old 35mm plastic film cans that hold patches pre-soaked in Ed's Red. At the end of a range day I'll pull one wet patch from chamber through to muzzle. Gets a lot of the loose crud out and leaves the more persistent stuff wet with solvent. When I get home and make Bore Snake passes, I'm done quickly and it takes a long time before the Bore Snake needs a wash.
I've also made one for any friend who has ever seen mine and asked, and I'm nowhere near exhausting the spool of monofilament I bought many years ago.
FWIW