Hoyt nailed it I have Stickhunter's .505 here on loan, have shot it quite a bit. It has enough recoil to cause your body to leave your head behind temporarlily, but this is not to say it's mean. The recoil is reasonable, mind you for those who's current comfort zone is .300 Win Mag etc, it is a significant departure at somewhere around four times the recoil of a .300. It gets your attention, however focus on the target, pay attention to your shooting position, and it's just another rifle. If you've ever had a flinch proceed with extreme caution as it could very well ruin your shooting for a long time. I had a flinch from .375 H&H when I spent too much time at a bench testing loads once that took me about a year to shed, and .375 is exceeding mild in comparison. Relax, think of your target, pull trigger and absorb generous energy into thy shoulder. Smile.
Here's the write up, including penetration tests of .375 H&H, .450 Rigby, .470 Nitro, and .505 Gibbs on stacks of spruce planks.
http://www.morrisonarms.com/2014/11/beautiful-nightmares-and-the-stopping-rifles/
And a live shoot of the same chamberings from the shooter's perspective, and a little 7x57 with "conventional" recoil at the end for comparison. The perspective is guilty of making the recoil appear quite dull, all except the .375 are lively but perfectly manageable for those accustomed to .375 level recoil for a good while.