x2 for loading up a bunch of different loads before going to the range. Just make sure you mark each load, and that you don't loose the little slips of paper you've got your load notes on
A stiff breeze will throw off a beam scale, as well. A beam scale is no less accurate than a digital scale, and is just as susceptible to wind/surface movements as the digital.
I can only imagine trying to keep your charge consistent on the range, as I know the tables at all of our local ranges are flimsy, wobbly and would be very detrimental to getting an accurate zero on the scale.