I had no clue the .22-250 was that effective, in my game deprived area the .22-250 cartridge (garden variety 1:12, 1:14 spin) is just hauled around in the pickup with the hay hooks and fencing tools. Used on ground squirrels, jacks and coyotes. I gotta get out more I guess.
I have also used the .22-250 in South Africa, culling big game for meat--which is legally sold over there in supermarkets and restaurants. Was on a month-long cull hunt (with some trophy hunting thrown in) in 2007, and my PH eventually asked my hunting partner and me if we'd like to try his culling rifle. It was an older Sako .22-250, at that time on its 4th barrel, and had killed around 12,000 springbok, which are about the same size and color as pronghorns, along with considerable larger big game.
My hunting partner and I switched the .22-250 between us all day, and killed several springbok, the longest shot one I made at around 500 yards. But once when it was my partner's turn we ran into a medium-sized kudu bull, and he killed it too. None of them were head shots, but typical heart-lung shots.
The bullet and load was nothing special.
The PH also owned a local sporting goods store, so could get stuff wholesale. His favorite culling load was Winchester factory ammo with the 55-grain pointed soft-point.
I seem to recall he also sold the once-fired brass in his store.
