I have a rcbs rockchuck press and dies and am noticing some inconsistencies with my C.O.A.L. I am getting a margin of error of plus or minus .0015. This leads to a difference of .003 at the extreme.
I am measuring from the ogive so it shouldn't be a variation in bullet tips.
What I am wondering is.. Is this normal and if not what are some possible causes? I am certain the die lock nut is tight.