If its the Bounty Hunter Im thinking about you have a piece of history that will still produce finds. If its the new one, no worrys they work the same. I would say at a low setting you could get within a coils distance of large metal. Try placing a nickle dime and quarter in the dirt a few inches of a fences to see what you can get away with. Your more experienced detectorist know to hit the edges. I always use this coin method to test new dirt. I have a small container of finds like gold and silver rings to test my detector and coils. Things do go bad, and I swung a broken detector for about 3 months when I got started. Old post are a good spot to look for buried caches. But you will need a detector that will go that deep. While modern caches will be large plastic buckets, your mason jar and tin boxes of yesteryear are a challenge even for a modern detector. Your better off with a probe. I plan on getting a probe and a gold detector soon. But already know there is limitations with any equipment. I still own my Bounty Hunter 202 which is not much more if any than your detector. There is some minor cosmetic differences, and you may be analog where mine is digital. But frequency and range and depth is about the same if not equal. I would always try a hasty test garden till yoru used to what you can get away with.