Depends on how hot the load is, case design and brass hardness. A case with a lot of taper like the 220 Swift may need it every time especially if it is in a maximum sized chamber. A cartridge like the 280 AI could get close to ten rounds before needing it.

I do it every 4th loading for consistency and before it needs it. This is also when I anneal so it gives the cases a new lease on life.

"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