re: Best deer rifle, caliber, setup for whitetail?

took two big does this year with a .270 at 150ish yds and over 200 yds - A-bolt with Nikon 3x9 shooting Hornady Custom 140gr. Missed one at 225ish. The miss was on me- to quote another poster, calm and comfortable shooting posture on longer shots is key. I zeroed the rifle at 200yds w/ 1" groups of 5. so I know it was me that missed. The two I hit, the bullet went right where the crosshairs were aimed, they fell over dead, not one step. First deer killed with this rifle as I normally use a 243 or a 300 wby. the trauma shock to the thoracic cavity looked like hamburger stirred up in red jello.