Mick, good to see you taking off time from those big walleye. We're pretty much shut down on the coyotes now with this heat. Might get chance to slip one in during July, but looking doubtful.
I'm going to suggest that you go the other way with your 223. Instead of the heavy 77 gr. hp bullets, try dropping down to 50 gr. I'm guessing your velocity with the 77's isn't fast enough to really get them to open up and give that hydro-static shock effect which kills so effectively.
As you know, I'm only shooting a 16" barrel on my AR. I get velocities around 3,200 fps with the 50 V-max and it hits pretty hard as you've seen on my videos. I can't say I've never lost one with the 223, but I also can't say that with the 243 which I agree is a hammer.
Anyway,that's my suggestion for you to give a try when you get back into the coyotes and give the walleye a rest.
