I had a friend who was practicing with his new .416 for his upcoming Cape Buffalo hunt. He was using it to shoot out of his second story window at ground squirrels in his pasture. Any squirrels that he missed got new holes to hide in.
To specifically answer your question, it is my understanding that the .22-250 was originally developed as a varmint cartridge, and with the right bullets it has been successfully used on deer sized (and larger) animals. I've shot both mule deer and antelope with mine. I have friends who have shot elk and buffalo with theirs.
And the .25-05 was originally developed as a deer cartridge that would also work well on long range shots on varmints on windy days. I've used my .257 AI, which is balistically similar to the .25-06, on everything from prairie dogs to elk. It's my favorite deer, antelope, and bighorn sheep rifle.
Jim Zumbo, Craig Boddington, Ron Spomer and Wayne Van Zwoll are all solid contributers to the modern hunting literature. Through their gifts (both hunting and writing) they make us better hunters. Whether it is letting us learn from their mistakes or by teaching us new techniques,they help us harvest more game. But I suggest looking to the oldies, the fathers of the outdoor writing craft, to learn tricks that you might have not used.
I chose to shoot the 270 winchester because I grew up...