Most people find their gun will like the bullet something like .010" to .030" of the lands. This is easy in the single shots, varies on bolt guns because of magazine restrictions, and just about impossible on lever guns. Of course switching bbls is basically like switching to a whole new gun which means re-testing lengths. Its the beauty of reloading, every gun is its own indivdual with likes and dislikes.
Good day,
Brian M.