I ran across this video of some folks, at what appears to be a range outside the US, shooting the .577 Tyrannosaur:
You can find some background on the round here:
As A-Square loads the cartridge, it fires a 750-grain bullet at 2,460 feet per second, for muzzle energy of more than 10,000 foot-pounds. For the record, the case will hold 180 grains of H4831! No other company loads the cartridge or makes the brass, but since brass, bullets, and loaded ammunition are once again readily available from A-Square, securing a supply is less difficult than for many other big cartridges.
Jim Smith, the new owner of A-Square, says the first question anyone asks about the Tyrannosaur is “What’s the recoil like?” Since there are a couple of videos floating around the internet showing several people being thrown across a room when firing it, your long-suffering correspondent would like to assure you that it simply is not like that.
The Hannibal rifle employs Art Alphin’s “Coil-Chek” stock, which minimizes recoil in heavy cartridges through proper stock design rather than gadgets like muzzle brakes and recoil reducers. However, Art conceded the Tyrannosaur needed something more and put three reducers in the stock. So equipped, it weighs about 13 pounds.
10,000 ft-lbs of muzzle energy? Holy recoil batman! But hey, if your goal is a last ditch defense against a charging elephant, I’d wager you’d need every bit of it. Now I really want to shoot one.