50/90 and 50/110 cases are quite different. The 50/90 is longer (2.50”) and wider at the base (0.565”) compared to the 50/110 case (2.40” long and 0.548” wide). The rims are different but that’s not an issue - just use the correct shell holder for each case.
There are no SAAMI specs for either case, so there is a little variation in specs between manufacturers. As it turns out my Lyman 50/90 dies are fairly tight and you could neck size and neck expand 50/110 cases using the 50/90 dies, however you would need to trim the bullet seating die 1/10” to crimp bullets in the 50/110 case. If you run hot loads you might need a 50/110 FLS die.
