Originally Posted by Dale
If you are so interested - go ask the manufacturers.
One of my Leupold 6.5-20x40 Vari-XIII scopes I have owned since 1990, it was second hand then. I have used it extensively and dialled extensively since owning it - result no loss of performance. I have a Mk4 that I bought s/h in 2000 - seen lots of dialling since I bought it - no signs of problems.
So what does this practical, hands on experience suggest to me?
It says the scopes were designed to do the job and they do it well over many years.
I don't doubt what your saying about your expensive scope's ability to withstand years of dialling, but my original point was that NO scopes are designed to be adjusted over 50 times an hour as they are when dialling for FT.