Did you buy this used? Anyway, I'd take a minute to find out what twist it is.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
US Army 1966-69, VFW Life Member, Retired Geek
Plain old M193 ball (55 gr FMJ) is as good as anything out there for coyotes.
Ball ammo will do the job, just be sure to hunt responsibly. If you are hunting wide open areas they'll be fine. I hunt IL farm land and there's usually homes within a mile or two. The soft points will break up on impact whereas the ball ammo has a higher risk of ricochet. I use 55gr vmaxes in a 1:7 twist 16" barrel.
I would not skin and case a coyote pelt for what they sell for. We can get $50 dollars bounty for the lower jaws. That is a much better deal. The 55 grs. expanding bullets work well in the AR-15. There is no hard fast rule on bullet weights and twist rates. You must shoot different loads in you rifle to find out what works.