If you are asking how far to seat the bullet off the lands, then you'll have to experiment and see where the "sweet spot" is in your rifle. As long as the bullets aren't actually touching the rifling (may affect pressure) you can play around with seating depths. Many go down to .010" or .020" or closer, but if you're using Barnes bullets, they recommend not going any closer than .050". There's a sticky at the top of this reloading section on how to find the sweet spot for Bergers. Read that one. It works for most other bullets as well.
Most of the time I take the munufacture's recomendation and start moving closer to the lands. Sometimes it shoots good with a long jump too. I have a .257 wby that I think the bullet could eat a whole sandwich from the time it leaves the case until it hits the lands.
Just expeirment a little.
Chuck J