The common knowledge has it that closer to the lands produces the best accuracy. Thus, I’ve always just seated .03” short of the lands and went with that. However, not everything is “etched in stone”. A couple of years ago I had developed a load for my 7x57 using 145 gr. Speer HC, PRVI brass and RL19 powder - seated .03” short as usual. It produced about 1-1/4” groups which is more than adequate for my purposes. (deer sized critters out to 300 yd. max.).
Last summer I got to thinking that this load just might have better accuracy potential so I started farting around with the OAL. To my surprise, a .07” jump produced sub MOA groups at 100 meters. At first I thought it might be a fluke however more shooting confirmed my findings. Five 3-shot groups averaged .88”.
You just never know for sure until you try.

What man, on his death bed, ever lamented, "God, I wish I had spent more time at the office."