really its something you just have to play with to know for sure. in my experince most heavy jacketed bullets like to have some jump into the lands and most thin jacket bullets (match grade stuff) like to be right on the lands or push in. I would guess the Amax 30 cal would like to be real close to the lands but again you really just need to play with it and see. My 6br liked the 105 Amax directly on the lands. .010 off the lands it grouped around 2" at 400yds, .010 in the lands it did the same, kissing the lands it shot under 1" at 400yds.
hope that helps some
steve