My opinion is as follows: I don’t like short 5.56 at all. I’m not even really fond of it in a 16”+ configuration but I do hunt coyotes with one. This isn’t to say that the round with the proper bullet isn’t fully capable at reasonable ranges. It is. But it’s let me down and I’ve had close second hand experiences that gave me a poor impression of it for most game.
I have 3 300blk weapons; a 16” AR, a 9.5” AR pistol and a 16” Ruger American Ranch. They all weigh about the same plus 9oz on the end if I have a can on it. I shoot supers out of the 16” AR, and subs and supers through the other two. I rarely hunt with subs unless it’s for hogs which I shoot in the head or neck. This round has not failed me once in sub or super. My go-to supers for hunting at the Barnes Vortx 110gr. I’ve killed a few deer and a bunch of hogs with this round including two hogs over 250# at beyond 200 yards(one with my 16” AR and one with my 9.5” pistol) both DRT. No exit wounds.
The pros for 300blk are: around 30% higher kinetic energy at a given barrel length over 5.56, fires super and subsonic rounds interchangeably, somewhat less muzzle blast in short barrels and lower felt recoil. It’s also a dream if you reload.
The cons are loaded ammunition is more expensive than it should be, the best bullets are hard to find, the ammo is heavier.
If I were willing to stock another round I’d be looking hard at a 12” 6.8spc. But I also have a 16” 6.5Grendel so that would be too redundant.