I've used quite a bit of H4831 since the mid-'60s and have infrequently used the SC version since it's introduction. If you have a favorite H4831 / H4831SC handload, it's best to chronograph a few rounds and also check accuracy and point-of-impact after opening a new keg. A powder charge might require adjustment of a grain or two, up or down, to get the same performance level of the original load.
We're told all powder lots vary at least slightly. Sometimes the variance isn't enough to even measure, but it's worth the trouble to verify this. In a .25-06, I've found the difference between two lots of H4831 was worth about 100 fps using equal charge weights. With my latest batch of H4831SC, it takes one grain less powder to get the same velocity as a recent batch of regular H4831 in a 7x61 Sharpe & Hart rifle.
Hairsplitting, maybe so and sometimes it doesn't matter anyway. Just depends on how far one wants to go in reproducing a good load.
