Jake if the arrow is hitting the shelf hard enough to remove the finish and cause nicks, I'd move it up at least 1/8" inch first time, you may even have to move it up a little more, try using a dry erase marker on the edge of the shelf to check to see if you got it right, and check periodicaly too, I have a bow that has went from 3/8ths high to 1" in less than a year,don't know why either, same arrows,same release, same me,same tiller, heck even using the same glove, puzzler for sure.......................Steve