Most seem to run from 7 to 1 o'clock. I'm not that familiar with the series and wonder if this was something more peculiar in 1916 over other years. I know design changes were made, but those wouldn't have that effect. So is it just metal mix?
I can't speak for the particular example you have here, but I know alloy mix, particularly at branch mints, was an ongoing issue in the teens and twenties.
I think it's more interesting that you've noticed a directionality in the striations. I would think they'd tend to be somewhat random in orientation as the planchets get jostled about before minting.
That makes sense. There were over 1900 1916 buffalo nickels on eBay that I was looking at. Perhaps my observation was made on too small a sample before vertigo set in.