Hey gang, any tips on how to find the sweet spot on a coil? Basically I'm trying to determine cold zero in shooting lingo. There's about 6 inches of snow on the ground where I live, so it's gonna have to be Something indoors. Is it as easy as listening with the headphones for the loudest signal? Do I go into pinpoint mode or stay in discriminate? Sorry for such a rookie question, but hey I got to learn!