Fred,
Steve Timm has done a lot of Coyote hunting with 223's using 40 gn bullets. So, I decided that would be the route I'd go with my 223, and got some good accuracy too. I just never shot bullets heavier than 45 gns in my rifle.
I had to buy TAC from Natchez as no one locally carries it.
It sure works wonders in 223's my two 222's and two 222 Mags.
Don