I have been given the green light from my wife to get a new rifle this year. Kinda thinking of an HS Precision rifle, but not set on it. I'm hoping to set it up as a beanfield gun, specifically for shooting whitetails from 500 to 700 yards, from a bench. I can't decide on a caliber, trying to find the perfect combo of speed and performance, without breaking my bank. I had originally thought of a .30-378, but there may be something better suited to this task. I'd like enough down-range energy to kill with authority out to 700 yards. Any recommendations on caliber and loads?