The thought of hunting anything other than paper or large inanimate objects at those ranges makes me sick. I'm not a great hunter and I don't see a ton of deer, but jeez.

Where in the hell do you get a gun that weighs 72lbs? Especially one in 338/378?

To my knowledge rail guns don't even weigh that much, unless they are pneumatic.

I had a Weatherby in 338/378 and it was an excellent round, but too much for Arkansas deer.

I believe Harris Gunworks made a 50 BMG rifle that weighed between 11 and 14 lbs, looked really violent to shoot from pics I saw.