uniforming primer pockets removes brass, lowers weight, does not affect volume
flash hole deburring inside removes brass lowers weight, does affect volume
trim to length, removes brass, lowers weight...but as it is above the bullet does not affect volume.
turning necks, removes brass, lowers weight, but as it is on the outside, does not affect volume.
inside neck reaming, removes brass, lowers weight.....probably does not affect volume...depends on bullet seating...only you will know...
so if you chose to sort by weight, turn the necks, fire form...do all other steps (size to get oal correct)and then clean well and do your weight sort.
some short range guys say you cannot tell the diff with lapua and 6ppc....
mike in co