Here is a video of the largest center fire rifle ever made, the .950 JDJ by SSK Industries(Ohio). Only three were ever made.
This was the lightest, the carbine version , weighing in at 50 lbs. It shoots a .95 caliber 2,400 grain bullet at 2,100 fps using 240 grains of powder, which generates 25,400 f/lbs of muzzle energy and 277 f/lbs of recoil energy. Each round costs $40.
Fast Tube by Casper