How often should i clean my rifle?

Well, I can add to Heywood's answer. Use only a steel cleaning rod as brass, aluminum and artificial material gets grit embedded into the surface and will seriously erode your barrel. Steel cleaning rods are harder than those mentioned, but softer than the barrel. I have seen the military steel ones worn down a lot, but no damage to the crown by their use. Also, if you happen to patch it too heavy the steel rod will not bend or break.