When I was living on the east coast i cleaned them after each time out. One it was very humid out and two it was far inbetween each shooting.
when I lived in southern CA in the desert I would shoot almost every weekend and a couple weeknights at the trap range.
the trap gun, a beretta 301, would get cleaned when it stopped ejecting some where south of 1,000 rounds. Same goes for my Sig P220 Sport that would gunk up after about 600 rounds. But target guns are finicky so I do not mind that they stop. If my P226 ever stopped I would be very upset.
My 22 rifles would be used on a regular basis and would get cleaned when something else got cleaned. Usually a rainy weekend would have me in the garage all day disasebleing and cleaning, oiling, waxing and putting back in the lockers.
Now that i live on the coast and I do not get out every weekend I clean them after ever trip to the range. The get torn apart, cleaned, oiled, greased, waxed, and then put away in the lockers.
As far as hunting shotguns the water fowel gun would get cleaned and Waxed and the upland side by sides will get wiped down that night and then cleaned and waxed when I get home. Oh yea Last count was 75 guns plus or minus the air guns and black powder.