Are we down to recommending the .22WMR for big game now? Not only is it unethical, I can't think of anyplace where it would be legal. Even elephants have been killed with a .22 LR but that hardly makes it an appropriate choice. We've all read stories about how so-and-so got shot in the head with a .22 and live to tell the tale. Sometimes they didn't even realize they'd been shot for decades. Can anyone on here honestly say they've heard of someone being shot in the head with a .30-06 or .338 that's still around to tell the tale?
At some point, shooting over distance, the .25-06 becomes a 25-20. Would anybody seriously recommend the .25-20 as an moose/elk cartridge at any distance?
The big X-factor in the equation is the man behind the gun. We don't know if he's good, bad, or indifferent as a rifle shot. We don't know if he's cool calm and collected, or if he get's wildly excitable in the presence of game. We don't know if he has the willpower to turn down quartering or frontal shots at the only animal he may see over the course of a season.
This thread, and many others on this site seem to have devolved into a contest over who can shoot the largest animal with the smallest calibre. It's the bullet that does the work, and to do that job it has to penetrate. Momentum is what gives us penetration, and momentum is acheived by velocity X mass. Bigger bullets will penetrate better than smaller ones. The extra weight and frontal area give you a certain amount of margin for error.
I don't want a calibre that's adequate when conditions are perfect. I want a calibre that will give me some margin of error when conditions aren't perfect or when things go wrong. Misjudging range, wind drift, bullet deflection, or

shooters flinch can all send bullets to places where they weren't intended to go. We've heard a lot on this thread about how many animals were felled by small bore rifles, but not much about how many were wounded and lost.
I'm more of an O'Connorite than a Keithian, and bullet placement is everything. But we still need to apply come common sense and realize there is a practical limit on how small you should go for a given species. My line in the sand for game elk size and up is the .30-06.
If you need to ask, that's telling me you're inexperienced, either a new hunter or hunting larger animals for the first time.
If you're an experienced hunter with ice water in his veins, then you really wouldn't be asking for advice to begin with.