I used to clean my Anschutz three or four times a year. Lots of other competitors never touched theirs except when they were so clogged with gunk that you could barely shove a round into the chamber, but I liked to stay slightly ahead of that condition.
The highest-quality .22 ammunition usually has slime on it. That gunk will eventually cause problems as 100% of it does not go away when you pull the trigger. I've found this to be slightly more of a problem with Eley Tenex than other match loads, but it can happen with any of them after a while.
After a real-deal cleaning accuracy is effected, though. It comes back after 10 to 100 rounds, but it is an issue. If you did not notice it, it is because the rifle was still accurate enough to shoot to the edge of your abilities. If your abilities were more substantial, you would have noticed.
