Size then trim to spec.
The ones less than 1.285" can be trimmed to be equal as well to make the roll crimps consistent.
Measure the cases before sizing and then after to get an average.
I treated my eyes and time remaining to a good set of digital calipers not long ago.
The new little digital, Mitutoyo 500 series, for our loading chores and the old big one is for the Iowa's crew..