Yes, i understand the problem! Its a scary thing to work out to much from the bedding. For this reason i´m using the most times only the cork layers. Once i have found out the correct thickness and position it is easy to make some more layers and change them if they were worn out. And this takes a long time till they´re worn out. Normaly it is enough to change it once a year if you shoot it very often, if not it is enough to change them every second year.