I probably wouldn't shoot that far but I might be shooting into brushy areas and thought the heavy and slower bullets would do better than the high velocity bullets. In the early morning or late evening light, I might not see all branches in the way. Not like I want to purposly shoot into a thicket, just want a little insurance. I had a .338 at one time and it was a bruiser. I wouldn't think twice about that gun shooting long distances.
There is just something I want to do with a big bullet and like I said I don't think the 500 will be much help past 100 yards with it's accuracy.
I'm a 98% bowhunter and have been for the last 37 years but love the guns yet. There's plenty of people that like to tresspass around here and I thought about making the tower stand as a deterent. They'd never know if they are being watched or not with the tower stand being so visable from the location it will be.