Do you need to clean it all that often? I've got Bill Calfee's book (The Art of Rimfire Accuracy) and he mentions the build up of a lead ring at the start of the rifling that is supposed to aid accuracy, at least for a while until it eventually will adversly affect it and need to be removed. I don't have an accurate 22 yet (in he process of getting an Anschutz 1710) but have seen the lead ring in other 22s, not that it seemed to make a difference to the ones I saw it in but they weren't top of the line shooters.
