I would think for this to happen something in the press or the seating die has to be moving around, has to be! If the die is locked in and there's no slop in the press, it would be pretty much impossible for the length to be changing. But, if all your measuring is the bullet, bullet's can vary in length some, at least that's what I've read over the years. But even so the length in the die from the base of the shell holder, when every thing is locked down cannot change unless there is movement in the press or the die. I know that I don't measure to ogive, just something else to concern myself with. I measure to the bullet tip and use the same case and bullet over and over till I get the die set where I want it. After that, doesn't matter to me what the length to the tip is as I suspect it will keep changing but the length to the ogive can't, it's locked in. Even if the ogive move's on the bullet, the die still set's the ogive of the bullet in the same place every time assuming there is no play in the press or the die.

I think people go out and buy tools to measure things like this for measurement's that really aren't that important then go nut's when they find out they have been making less than perfect ammo for years and settled for it simply because it shot very well. So, how does the ammo your getting shoot or haven't you tried it because of this little discrepancy?

Last edited by DonFischer; 04/06/20.