I killed a bunch of prairie dogs with the .375 H&H while practicing for an iron-sight safari in Botswana 12 years ago. However, must admit to using a reduced load with the 220-grain Hornady flat-nose on the PD's, at about 2000 fps. This shot right to the same place as 300-grain full-power loads, and after taking a bunch of PD's out to 175 yards there was no problem in Africa out to 200+. The Hornady expanded dogs about like a 55 from a .22-250.

“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck