I hunted for maybe an hour and half at the old National Guard Armory. We've beat it to death for 40 years with a lot of different detectors, but on the south side the ground between the building and sidewalk is almost solid with trash and I thought I might luck up on a older coin. I've hunted it before with small coils, and pulled an occasional coin out, but today I used the Viper/5.5 inch coil in that area and got 17 coins. One coin was a recently dropped zinc penny, all the others were 4 to 6 inches deep, and other than the surface zinc and the coins that were under an aluminum can - described below - none of them gave clean signals. Except for a 1944 wheatie the other coins ranged from a 1964 penny to a 1971 dime. In one area I got a high coin range signal that I could still get with the coil almost knee high. I had swung over it numerous times in the past and left it because I knew it was too big to be a coin, but today I dug it just to see what it was. It was about four inches deep, had holes from me probing it in the past and looked like a smushed flat aluminum Vienna sausage can. I swung back over the hole and got another high tone signal that was a 1971 penny, followed by a 1964 and was still getting high tone signals There were 8 coins, 7 pennies and a dime, in the hole that were deeper than, and almost directly under, the smushed can.