About 20-30 mins. Used the 14 inch coil, coin mode gain 9 disc 2 and an audible threshold. The MXT ran very smooth with this setup. Think this school may get hit , HARD. I did find 2 pennies, one a solid 6 inches in goowey red clay that turned out to be a 1957 D wheat penny. They area is pretty clean and not alot of trash, anyways may be worth another trip with a little more time.
Ray
