Went digging for a while today an an old homeplace, using the stock 9" coil on the 70. Didn't find any CW bullets today(found 4 the other day). I did find 2 complete harmonica reed plates and a bunch of old post-CW rimfire casings. Anyway, my curiosity has prompted me to get the bigger med. frequency coil for a little added coverage and depth. Should I see a difference? Thanks