Seating depth query

[adam]

I have made my first batch of loads for the new rifle and am hoping to start testing them next weekend. My question though is if I find an accurate load or close to accurate, If I then start to alter the seating depth am I right in thinking that the pressures can change and I may loose the accuracy of that load?
I.e .... If I seat the bullet further out of the neck nearer the lands the pressure in the case will drop a little. So will I have to then put more powder in to match the pressure that gave me the originally accurate load?
Sorry if this is confusing
Adam

[giterdone]

What you ARE changing by seating the bullet further out is the Expansion Ratio (total volume inside the case plus barrel exposed to powder gases, divided by case capacity). I doubt seating the bullet further out is going to have very much effect on the overall pressure in that case, unless the bullet is touching the lands, however it may affect accuracy. Internal case volume varies from lot to lot, thats why it helps to sort and prep cases (of the same lot) by weight and not mix them before you try to shoot tiny bug-holes.