Txhunter58,
Your pretty much right when you say a bigger bullet especially in bore size has a different kind knock down power. The big bores have that U shaped factor on impact and wound channel. Where the lighter fast calibers have the V shaped factor on impact and the wound channel is spread out into the animal at a slower rate. Bullet design can also change this a bit. But the 30-06, 308, 300rum, 7mm mag, are all pretty much in the same V class of impacts and kinetic energy displacement as it travels through and animal. Any bullet weight that is heavier and slower is better at causing the U shaped impact and hence creating more of a traumatizing hit taking the air right out of an animal. Knock down power. A shotgun slug, a muzzle loader, and all your african sized calibers will for sure just put the hurt on an animal in a hurry. But rifle's pushing bullets around that 3000 fps mark or faster are going to react very similar to each other in performance on impacts and wound channels. The simplicity of knock down power is lost unless your hitting major bone. But the end result is still the same a dead animal it just might take a step or two and realize opps I think i'm screwed.
But when people compare apples to apples it just makes me shake my head and wonder. How much research and practical use knowledge is used before making statements like, a 270 is not worthy of it's place in the elk hunting world. And it has nothing to do with the 270 class of rifle itself just that mentality that energy and bullet size replaces accuracy on game animals. I've seen elk hit with almost every caliber out there and a bad hit is a bad hit no matter the bullet size or the caliber.
I like big bore rifles and muzzle loaders. I love putting the smack down on animals. I also love reaching out and taking the pumper right out of their chest at longer ranges.
In all defense of the lil mighty 270win my favorite elk rifle that comes out of my closet is my 300 win mag. So you see even though i've killed plenty of elk with a 270 win I choose my 300 win mag over my 270win for one reason. My particular 300win mag rifle is one accurate sob with the loads I have for it. Not because of power. I even take it to the bench rest competitions. Having faith in a particular rifle is so much more rewarding than data and ballistic charts. Beware of the man with one rifle for which he knows it well. hehe
But if i was to start all over without any experience in today's modern world of rifle makers and calibers to choose from I would be lost myself in trying to make a decision on which one would suit me best. There is so many options.