RE: How early can u use a grunt call/antler rattling?
Again just make sure not to rattle to early, because you will just spook the heck out of the deer. The best time forrattlingis about a week before the peak of he rut and go till about a weak into the post rut.
When the rut is getting close and you see bucks start to scrape and rubs are popping up, start to grunt at them. Once the rut is over make sure not to use aggression grunts and go more toward contact grunts.