From Hornady customer service. A little more equivocal than whoever WDEA spoke with.
"Thank you for writing in to us. The main difference between the ELD-Match and ELD-X is that the ELD-Match has a thin jacket and no interlocking ring to hold the jacket to the lead core. The ELD-X has the thicker jacket and the interlocking ring on the inside. We don’t really test the ELD-Match bullets terminally, but the fear is over-expansion. There are some that use these bullets for hunting and are happy with their results as there has been many that used the A-Max (the ELD-Match predecessor).
