I go to a really good outdoor range for when I want to shoot long range and @Craig6 is absolutely right a .308 won’t get you to a mile unless you just lobbed up a hail Mary and it just happened to land up there amongst em.
I know when I am shooting at 1,000 yards I am getting everything out of my .308
If you are just wanting to say that you hit a shot at a mile, it’s probably cheaper to find someone who has the gear and expertise to get you to a mile. You are talking serious investment when you want to start talking about hitting at a mile.
Alot of factors go into making a shot at a mile.