Look at how many rounds it takes to shoot out your barrel. Stop somewhere short of that. I believe that you will never wear out a .22 calibre barrel.
I had a friend who “tested” a Marlin Model 60 to failure. He estimated that he’d pumped close to 30-40K rounds through it without cleaning it. It never failed to fire until the mechanism became so worn that it no longer lined up or fed rounds correctly, then he tossed it and bought another one.
The bore on that thing always looked as it did the day he got it. Didn’t wear appreciably at all.
If you take care of them and oil them occasionally, just about any .22 will last longer than you will.