I also use fishing line with napier patches cut about 3" long (.22 shorter for .177), the first patch is lightly oiled at the front if it comes out v dirty I repeat and then continue to pull dry patches through until they come out clean. Use fresh patches each time and I clean any oil left around the loading port as i'm not a fan of smokey spring guns. How often do I clean the barrel ?, maybe every 2500 shots or more unless I change pellets, also when I'm not knocking over targets.
AA RN10 Mk2 .177 + Sightron 10-50x60
Weihrauch HW97K .22 + Mamba Lite 4-16x44
BSA Superstar .22 leup copy 3.5-10x40ish