So, again I'm not going to be out tomorrow trying to shoot animals at a mile...rocks and steel are in my plans though...
Obviously your first post led some to believe a 1 mile rifle was meant for 1 mile shots at deer. I wouldn't say a person couldn't kill a deer at 1 mile, but that is a long long distance, and it would take really good equipment, extensive load development and practice, etc, etc, as has been mentioned. Nobody much cares if bullets are flung at vermin at extreme long distance. Some are pretty sensitive about the increased liklihood of wounding and maiming shots on game animals.
Anyhow, now that you've clarified your intentions I'd think that issue would be dropped, and hope that you end up getting more productive comments that we can all learn from. Becoming profiicent at 1000 to 1300 yds is still a very high level skill, requiring very good equipment. All I've done is read about the ultra extreme long range approaches in the one-mile plus ranges, enough to know it gets exponentially (much much) harder to connect and requires even more specialized equipment to be a contender. Quite a few can offer advice on 1000 yd shots. Nobody really discusses one-mile shots on big game animals - even on this Forum - which specializes in Long Range hunting. They either don't do it, or they keep what they do to themselves.
Good luck to ya. Get good at 1000 yds first and then pursue your ambitions as you desire past there.