Reason for asking this is because I did not think people would jam up in the lands as this increases pressure more. And assuming ammunition is more accurate with almost full case or in the upper velocity range and this is where we attempt to find accurate loads, jamming into the lands will increase pressure even more.
That's an assumption that would be argued by many. I've seen plenty of loads that were pretty far from 100% load density that were very accurate, and I haven't found that velocities in the upper velocity range for the cartridge tend to be more accurate. Accuracy is all about harmonics, a load with the widest "node" will usually be more accurate. Fastest and fullest case doesn't mean most accurate, that's an old wives tale that doesn't hold water.
If you're going to seat bullets into the lands then you need to work up to it, you don't want to take a full house load worked up with a .030" jump and seat it into the lands, it probably will be a little hot then although the amount of extra pressure seating into the lands generates is often exaggerated. If you work up the load with a chronograph & the bullet kissing the lands you'll likely find it'll take slightly less powder for the same velocity as a jumped bullet. It's not a problem so long as you recognize the limits. Pressure's not a bad thing, too much pressure is.
