When testing a new contender bbl. I clean every 5 rounds all other contender bbls after each session.

22s and 9mm when ever they start losing accurracy or if I start getting a lot of misfires I' ll clean the bolt(s)

hunting rifle at the end of the season. If I shoot it in the off season I' ll clean it after the shooting session.

All I use for cleaning is MPro-7, most of my bbls are conditioned now and cleaning them only takes a few minutes so it ain' t no big chore.