98dyna,
I recently purchased the Hornady Lock N Load bullet comparitor (for setting OAL and their headspace comparitor. I have found both invaluable for determining how much shoulder setback is required for proper chambering and for setting the bullet correctly off of the lands.

My next loadings will be the 160 Sierra HPBT Gameking and various powders. On prepping the brass, I found the WW (the shells with the huge group) had cartridge lengths all over the place while the Federals were extremely consistent! The Federal case weights were also very tight. I have yet to weigh the WW hulls. I can tell you, they are all the same length now!