Anytime is a good time to start ratiling during the season in Sept. This is when the bucks begin social sparing. Dont go in there and slam the horns together like a brawl, but just tickle the horns together, and be ready. Rattle for abotu 20 seconds and wait about 20 minutes, you dont want to spook that big one that may be bedded down no more than 50-100 yards away from you.