Hello all I have a quick queston about changing brass. Currently I am shooting crappy federal brass out of my 243, but yesterday I bought a box of 100 lapua brass. I know all the tollerances are far superior so how much is the new brass going to affect my load ? am i going to need to start over with load development? or will they be close? and with quallity brass like lapua do you see much of a change in accuracy between new and once fired? keep in mind I always f/l size anyways.