Make sure ever station is full when your measuring/setting up your OAL. If your setting up your OAL while just using the seating station, then once you start cranking out the rounds and using all the stations (most importantly the sizing station), the OAL will change. Your OAL should stay with a +/- .001. Unless your seating die is seating the bullet off the O-GIve and not the tip of the bullet. In that case, I'd have no idea, but deviations would go up, since handgun bullets just aren't made that precise.
I will try this... Thanks. I am loading SWCs and had to swap the seating die around from RN.