Probably the single most important lesson one should learn is not to shoot. Also seems to be the hardest based on my observations. And with all the technology its only getting worse exponentially as hunters try to buy skill at Cabelas.
You would seem to be drawing all the wrong conclusions from the posts here. "More practice shooting". No you need more practice hunting.
I may have to take a shower after typing this but Buzz is exactly correct and his follow-up with pics is gospel, of course I've never questioned his hunting acumen, only other things.
Learn to track, learn to call, better yet learn to be patient, learn to plan a stalk (primary) then learn to execute it. When your stalk peters out at 50-125 yards, the set up in your hands will not matter nearly as much as the hammering in your chest and the trembling in your hands (take a rest).
On a positive note congratulations on your follow-up tenacity, it indicates you are worth helping, most are not.
My favourite rig is pretty much same as yours, scope sighted bolt .300, but probably 40-50 of my elk could have been just as well shot with a .308 or even my open sighted 45-70. More than 50% would have been fine with a .243 but I'm a sucker for a big hole in the end of my barrel, but not because it is needed, just personal preference.