Every so often I sit down with my Etrac detectors and do some Air tests to check if every thing is working correctly. I was good until I hit some War nickles with a S mint Mark. You expect War Nickles to hit just a little higher maybe 12-14 or 12-15 but these all hit at 12-29 to 12-32. This means I have been missing one of my favorite coins, War Nickles. I usually start Discrimination at 12-33 up to cut Pull Tabs. I checked the P Mint marks and these all hit at 12-14. Pays to check but now I need to re-hunt a bunch of places.