Found a few memorials and a lady's pocket mirror case, at a old home site, and who says you can't tell between bottle cap or penny, you got to know your machine, and I haven't puled one yet, but I have used the ace350 series for along time, but hey it's a great machine case closed, AC
Your not going to find alot of home sites littered with bottle caps....try the local parks or ball fields next to bars and let me know how many bottle caps are in your bag at the end of the day
Yeh it must its only my 1st year and i got a 350 around 4-5 months ago....the only old park i have found has been a good learning ground its produced over 30 silver .....ive dug about every bottle cap in there already since they all ring so good ...same with rusty beer cans they also ring high tones...ive worked the little park down to foil reads finding the war nickels and buffalo's proved tough since it would never lock onto a nickel it would be a bouncy foil pull tab/nickel read