Still - what private citizen needs access to that kind of firepower?
Recoil.
Ever fired a 30.06 vs AR15? Standard rifles & shotguns recoil like mthrfkrs. Dang things
hurt. The recoil on an M16/AR15? It's a tap. 2 finger tap to your shoulder. That's it. Versus kicking like a mule & leaving bruises at best and torn up muscles & connective tissue at worst (if you're holding it all awkward or have been caught by surprise and don't have time to seat it properly). Unless you're a total muscled badass (& I'm not, I'm a big baby) that kick affects both accuracy & willingness to put in the practice to be able to hit what you're aiming at.
My 2nd favorite long range target acquisition rifle is a bolt action Remi 700 series (1st favorite is something British that I borrowed once upon a time and really need to figure out what it was. Sweet and smooth as silk, that rifle. I don't know if you could miss if you tried.) Even, so... If I were hunting? I'd want an AR15. Not for the hunting, but for the using it on the fly. Because when you're out in the woods... Absolutely every single predator out there is bigger, badder, and better armed than we are.
I live in the city. There is very little reason for me to be armed, here. Human inhabited areas are virtually free of predators and problems outside of our own making, and we've got police in spades. Although, here on a PTSD board, I think we're maybe overly familiar with those particular problems. I keep a shotgun loaded with rock salt (stings like a mofo, unless I'm close to you, in which case even rock salt will take off a limb) for intruders (my house was broken into 2-3 times a week for awhile)... Although racking it is such a distinctive sound that the noise alone usually sends people packing. Even so, unlike pistol & rifle rounds, bird & buck shot isn't going to go through my walls and hurt my neighbors. Rock salt? Again, unless I'm firing point blank into the drywall, I'm not even going to do much more than ding the paint. Less lethal rounds can still kill a person (I prefer Canada's use of the word less-lethal, rather than American non-lethal, because even blanks can kill if you're close enough, much less rock salt or bean bags). Even so, I usually grab the machete, mag light, or a kitchen blade if I'm investigating something. Pure bias, firearms are loud, especially indoors, and I don't own suppressors for all my weapons. Nor do I keep most of them at home. Because, again, I live in the city. I don't need them.
Jump on out to the country? Much less the back country? Whole 'nother ball game. These aren't manicured greenspaces, parks, and back yards. Not even the ghetto. This isn't "The police didn't bother to show up for an hour!". This is, maaaaybe someone might find your body in a few months, or a few years, but probably not. There's no back up. You're on your own.
A 5.56 round (or even a 7.62) isn't going to stop a bear. It's just not, unless you're both lucky and good. Neither will most other rifle rounds. Moose, bear, even the big cats... They've got fur & thick skin & fat & muscle that protects them like body armor. More than likely, unless you're using a .50 cal round to their head, you're going to need to put a few rounds into them. Once upon a time, I used to be pretty good at spine-shots. That needs constant practice, and I simply don't have the money to be putting a few thousand rounds a week downrange. Disconnect the CPU, and your target drops. Anything less? They're still going to be coming at you, if they're a pissed off wounded predator, whose meal has just stung them like a bee. I do
not want to be f*cking around with a bolt action rifle, with narrowing distance between me and 500lbs or more of sharp teeth and claws or hooves and attitude. Nor do I want to depend on their being afraid of a bee sting and takin themselves off elsewhere (happens, sometimes). What I want is to be able to put 3/6/9 rounds into them...fast.
Which means semi-automatic & recoiless. Not bolt action and one arm dangling limply at my side if I gaffled the shot.
Quite honestly? Same goes for people. Most people are pretty decent. But back of beyond, 300 miles to the nearest cop-shop? I really don't want to be depending on the milk of human kindness. I've met some really awesome hikers, hillbillies, & off-grid sorts back of beyond. :) I've also met some serious f*cktards, who do not play. :meh: If I've got my bolt action remi? Most people in the country know that I've got -at best!- one shot, maaaaybe two. It's moderately easy to dodge a wild shot from a scared shooter. Most people are lousy shots, for real, especially when they're afraid. A "hunting rifle"? Shrug. They can take me. They know it, and I know it. AR15? :D I could be an absolute crap shot (I'm not), but with 30 rounds in the mag, and another 30 in reserve, I can have 60 rounds to play with in under a minute. If I've cheated, and modified for 3 round bursts, in less than 30 seconds (and they have no way to know if I've cheated, so the assumption is always that I have). As long as I maintain proper distance? Unless I'm out both numbered and outgunned, I can take care of myself.
While most people in this country live in cities/ manicured suburbs, where there really is no earthly reason (outside of a zombie apocalypse ;)) for ARs... Millions live in the country, still. Millions more go play in the country. Bolt action? Totally fine, as long as all you come across is Bambi.