I clean if going into storage for any length of time as we have a humid climate. If not I clean when I change loads and before I hit 100 rounds usually before this though. If your shooting on a regular basis you can wait till accuracy starts to suffer before you clean. I got rid of all the barrels that are prone to fouling so I probably clean more frequently than I need to.

"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli