Re: ar 15 for coyotes
There are many great AR options. IF you get a shooter, I do not think you can find a better coyote rifle. I have had many that did not shoot well enough for any but short range coyote shooting. If buying used, which I would suggest, I would hope to scope and test prior to buying.
5 shots in 1.5" at 100 yards or better yet, 5 shots in 4.5" at 300 yards. That would be the largest group I would accept. I have seen many that would not do it, and many that would far exceed it.
As most coyote killing is at well under 400 yards, I would not get a fast twist, heavy bullet barrel. I would consider a 8 or 9 twist and shoot 55 or 60 grain bullets. Over 400 yards they will shoot flatter and kill well. If you intend to shoot LR you will need a 7 or 8 twist and heavy bullets, but you will loose some trajectory in the process. And very few will actually kill beyond 400 for coyotes I think.