One caliber for all? is it possible?

Originally Posted By: crapshoot17 Remington, 20 practical,

Used both in an AR, You will have to place your shots, don't expect to bust up sholuder bone with these two.
Originally Posted By: CoyotejunkiOriginally Posted By: crapshoot17 Remington, 20 practical,

Used both in an AR, You will have to place your shots, don't expect to bust up sholuder bone with these two.

And bullet selection plays a lot into their effectiveness too but can be great for saving fur.
My old hunting partner shot a lot of coyotes, bobcats, and grey fox without blowing the hide of them.
I am going to throw in my vote for the 17 Remington. I've shot a lot of greys and bobcats with them and like Coyotejunki said, you've got to be a bit more precise on you shot placement and like crapshoot said, bullet choice is crucial. I personally run 20 and 25gr hollow points. This allows the bullet to get through the hide before it begins expanding to prevent splashing, but then it expands EXPLOSIVELY. It can work on coyotes but then shot placement becomes even more critical. But I have two of the hunters on our team that have even taken javelina with the 17 Rem.
Talk to DAA about some of the heavier custom/semi-custom 17 cal bullets to hammer coyotes.
I hated the performance of the Hornady hp's on coyotes when I had a 17 Remington AR upper. Probably why I sent it down the road.
Since OP asked for AR15 cartridges, I'd think 17 Remington would be a poor choice. Brass recovery in the field for one. And spotty component availability in general.

My 17 Rem was pretty tough on our small grey foxes with Hornady 25gr HP. It blew some good holes more often than not. I would not recommend it for grey foxes.
In .223 I have had excellent performance from the Sierra 40gr HV HP #1385 loaded to 3400. Hard to locate the entrance and no exit.

In 6x45 I like the Speer 70gr HP & Sierra Blitz 80 gr SP. They usually exit but the exits are small. I also use these loads for deer.

In .300 Ham'r I like the Sierra 135 gr HP, Speer 130 HP and Hornady 135 FTX.
This is a 135 FTX exit.

For a do it all rifle / load I use the .300 Ham'r. All of the bullets I listed are loads I use for deer and they have performed well on Yotes as well.

These 2 were taken the same morning with the Sierra 135 out of the Ham'r at 2400 fps.
Out all of 3 that I own..

204 Ruger
223 Rem
17 Rem

I’d have to pick the fast 20. I’ve shot everything from coons to deer with that rifle, and never had a problem. Bullet selection and placement has a lot to do with it too though.

I’ve killed countless cats, foxes, coyotes with no fur damage. But I’ve opened up a few too by accident. It just happens.

I’ve got 3 other rifles that if I’m just targeting coyotes I’ll take my pick for the day. But if I feel like we’ve got a good chance at a cat or fox country, I’ve always got that 204 with me just for it.
I sure like those 204 Rugers. Shot a BUNCH of Praire Dogs and a few coyotes, on the coyotes I did not experience major fur damage, primarily use 32gr. Vmax about 3940fps, if I was going to target coyotes, I would move up to 39gr SBK or 40gr Vmax ( if 40s will stabalize ) I have 2 with 1:12 and they both shoot the 39gr very good, have not tried the 40s. Recently got a White Oak complete upper in 204R, 1:10 so I am pretty sure it will handle the 40 and maybe even 45s if needed, only been able to shoot paper with the AR so far, but holy smokes does it shoot. 204 with a suppressor is less noise and recoil as a 22 LR, can see your hits and the flips..makes em great green chilli!