Would you like a sore shoulder? SSK Industries has just the weapon for you, a rifle firing a .905 caliber bullet. The bullets alone cost $40 each. See the article in the Daily Mail (U.K.). The thing looks like a mini-cannon. Hat tip to Lucianne.com for the link.
The Brits once made large-caliber rifles for elephant hunting, Holland & Holland was a leading constructor I believe. I also remember the term "nitro express" was associated with big game super rifles.
Come to think of it, someone is now making a rifle which fires the .50 caliber M2 Browning machine gun cartridge. That one punches holes in trucks and buildings, from far away.