Ugh! The question of where to start seating always gets me. I don't like seating touching the lands because if there's any overlenght at all, the cartridge won't seat and the bold won't close. Then there is the added pressure issue. But maybe I'm missing something here, I don't know. I just never got any better results from kissing the lands than .005 or .010 short.
Also, from what I've experienced with factory ammo on at least 2 rifles, bullets that are far from the lands can be as accurate as well made hand loads close to or touching the lands. An example is Federal 243 Win. Both the 80gr HP and 100gr SPs are far from the lands and give exceptional accuracy - .25 - .5 MOA. So what the neck, I just used Barnes Book OAL for their 85gr TSX, and worked on powders from there. This is far short of the lands and yields excellent accuracy. Same with Sierra HPBTs...no accuracy gained by touching the lands but if they are a few thousandths too long (don't know why this happens), they're unusable til I get back home and push deeper.
So if someone is going to reload not touching the lands, do you set a good guess OAL first and then work through powder wts. or do you stay with 1 charge wt. and vary the length til groups tighten up? I usually do the first approach.