by no means am I an expert on this, but from a sorting standpoint, I have found some pretty drastic differences in years and case length. LC(13) almost all were 1.901-1.9015. I don't know enough to say those 1.901" cases are too short or not, but i have set them aside for now and am working with LC (11) trimmed to 2.00". that was a good length that didn't require culling out a great many short ones.
Another observation on SAME year dates, not all LC (11) are the same. I found a few, less than 10, where the head stamps were oriented opposite all the others. stamped information oriented to be read from the center out, as opposed to being read from the outside. Also the fonts were a different. Just saying the year is just a starting point, at least for me.