If I bought or built one, it would be relegated to more of a homestead defense weapon. And for some fun on the range. Also annoyance/destructive animal removal, etc. I wouldn't be taking it with me on a picnic or anything. Animals SHOULD be at a major disadvantage when you're out to hunt them as a food source or eradicate a problem animal. If you think an AR gives you the superior edge, by all means, use it. I'm not into "sport" hunting animals or anything, although I don't have an issue with those that do.
I look at guns as part useful tool that takes a little practice and training to use it well, and part of a bit of fun to try out new types ammo and other types of weapons. I am by no means an expert, and likely never will be. I own more Oldsmobiles than I do guns.
The rifle barrel should give a more stable success rate for longer distances, but it really depends on the setup and tuning of the rifle, and the skills of the shooter. I feel pretty confident with my 9mm pistol, but for longer distances, if need be, I'd prefer a rifle. I have a couple of shotguns, but they also have drawbacks. Regardless of what weapon you prefer, practice practice practice, with safety the paramount priority.
In the U.S.A., I feel it's MY right and responsibility to choose the legally-obtained weapon(s) that make me feel the most comfortable in protecting my family and property. Nobody elses'.
Using an tank would be ok if you wanted to pick up your prey as "already ground" if there was anything left to pick up. Easier to make patties out of on the grill maybe. 🙂