not from down there. from up here. Though there are enough of you up here that I can say 19 nearly perfectly.
I'm confident that all reports you receive will be similar. Good!!
There is no cartridge that will match it and an almost identical cartridge developed by another smith.
I have a 375 AM which will more or less shoot along with the 338 AM the advantage being, with 350 SMKs, maybe a few foot pounds of energy. Not really enough to have meaning.
Watch Shawn Carlock's Long Range Hunting video, the first one, noting the time for bullet travel on all shots. Pay particular attention to the long shot on the bear. Flight time is impressively short. Very impressively short.
Good luck on your quest.