What are the cartridges that DoD Has been using for a long time that have nothing to do with the infantry? The only one I can think of off the top of my head is HK 4.6x30mm, which the USN uses in a suppressed role for sentry elimination (allegedly, even if it does seem a very peculiar choice)

One thing I think we need to consider from a military context is that if an EPR style penetrator projectile is used, maximum projectile weight will be in the area of about 85 grains.

I am interested to know what you think the ideal civilian hunting applications are. Seems like it would be pretty good for people who want to hunt big game (mule deer, etc) at longer ranges with an AR15 style platform. I think it has more promise as a civilian round, to be honest.