Just a tip from a new reloader. I thought the same as you as far as accuracy stemming from seating the bullet out next the lands. I have a 35 rem that goes to pieces the closer it gets to the lands. I found that the closer I get to the minimum overall length the better groups I got until I got down to 1" groups @ 100yds. I don't know the reason, but I know I can't seat the bullet out too far and get results. My .250 SAV is about the same except I have a little more room to play with in that caliber. I am sure that the powder and components have something to do with it.