Re: .270 vld ?
The actual COAL depends on your rifle. Chamber, headspace, throat, throat erosion, etc all come into play on every individual rifle.
If I understand you correctly, then you are jamming your bullets .010" into the lands which is acceptable for some applications. e.g. benchrest, target, single shot. But, you certainly want to work up your load carefully as it could cause a pressure spike as compared to the same load with say .010" jump to the lands.
Also, keep in mind that it's often considered risky to jam bullets into the lands with a hunting load and/or in a repeater as you may accidentally pull your bullet out of it's case inside the rifle if you open the bolt after chambering the round and end up with a magazine and chamber full of powder.
Hornady and Sinclair make COAL gauge tools for measuring and there are methods for measuring similar to what you've done in order to fix up a dummy round that can be retained as a reference.
One technique is to seat your bullet long in an uprimed case and use a sharpie to color the ogive. Then, try closing the bolt gently. If you feel resistance, seat it a little deeper and color it again. Repeat the procedure until you are just able to close the bolt with the slightest scratches on the ogive. That would be you COAL to the lands.
From there, you can start working up loads with that COAL as a reference point and try various seating depths with various amount of jump. Berger published a paper about seating depths but I can't gte to their website right now. It's been referenced in these forums a few times.