I'll shoot a 50 shot range session on a 3/4" Tom Fuller black english flint, then usually get about halfway through the next Saturday range trip before I replace it...will have knapped it 2-4 times during those 60-75 shots...clean them and toss them into a jar.
Every now and them if I'm rained in or something, I'll sit down with a diamond cutting wheel in my dremel tool and cut a new bevel slope on them...takes about one minute per flint, and I'll get another 50 shot range session out of them.
