I've seldom found that any load shot best "on the lands". I normally start at .010" off and work from there, usually further from the lands, but I try them all, including "into the lands" until I find a load. However, a number of issues have arisen for me lately where I've decided that the lands are just a convenient measuring point and reference. Even after many, many years of reloading (55) I've recently found loads shooting as well, or better, at the SAAMI designated OAL. Only problem with that is the point of reference is too variable measuring from the tip of the bullet because of the differences in ogives of the various bullets. I've also found loads recently shooting quite well around .025" off the lands in a couple of instances, and another just yesterday at .040" of the lands. I used to tweak loads using different primers and small changes in powder charge at my beloved .010", and I usually found a load at that setting. I now believe you can find loads almost anywhere across the spectrum changing only one of the components, including powder and powder charge, seating depth, primers and bullet grip, but you have to do this only one at a time until each variable is exhausted. Where you start is just a point of reference, I don't believe there is any more magic in one method than there is in another.
