I am sure it has been asked and answered many times but looking for new fresh look at subject. I own an FN5.7X28 semi auto where ammunition goes for anywhere from $.40-$.60 per cartridge, so when I practice with same, I only shoot about 30 rounds in 5 shot increments with my friends. I tend to think that 100 or 200 rounds can be fired before cleaning is necessary--maybe more and maybe less. How many rounds fired should constitute a responsible schedule for cleaning a semi auto? Opinions? Thanks.