Finally figured out the 6" coil. Went out less than three hours in two parks yesterday, and nailed 77 coins, all clad. I was pulling out coins a the rate of one every two or three minutes! BUT, and this is a BIG BUT, I didn't dig ONE piece of trash! This coil is da bomb! It wasn't the mode or settings, it was simply how I swung the coil and how it SOUNDED. I got to the point where I knew it was a quarter, dime, nickel, or penny EVERY TIME. I'm really stoked. The more I use this amazing machine, the more I'm happy I purchased it.