Guys. Guys, Guys! We're all gun lovers here. Let’s stay united in our cause against the tyranny that would like to take them away! Too many times on here we get too involved with our own little soap box and soon forget the bigger picture. We are united, right?
Back to original subject . . . my personal feeling is that the gun manufacturers created some of these rounds simply as a means to sustain their own existence.
.300 WM, intro'd in '63 . . .7mm Mag, into'd in '62, ,338 Mag, intro'd in '58 . . . Relatively recent developments. The horse didn't ask for a new cart, but we get them all the time. Nowadays it's the "Ultra this and that. IT'S SO WE WILL BUY NEW GUNS!
Nothing like a "My mag's bigger than your mag!" conversation over a beer at the bar, right? I personally got rid of my big three mags and now shoot the tried and true .308. I have several deer and three elk in the freezer too!
Bottom line . . . they all work well in the hands of a skilled shooter.
The best gun made is the one you are the most confident in.