I have not loaded for .223 but I have for .204 and .243. For .204 gophers I use Speers TNT, they are cheap, will shoot MOA no problems at all, and are absolutely explosive on gophers. For coyotes I use Sierra Blitzking, a litle more expensive but incredibly accurate and the lighter ones make such a small hole you don't even need to put a stitch in. I use H322 and H4895. Both are excellent and reliable powders because of how consistent they are in temp fluctuations. Either of those would work great for whatever you decide to do. H322 is more for lighter bullets in smaller calibers because it burns faster. You can't go wrong with H4895 though. Shoot me a PM if you have any questions or anything about reloading. I haven't been doing it for too long but I can introduce you to some guys that have been doing it since the stone age. I also have some H335 I am not using because it shot like #### in my .243 so if you'd like to give it a try I can sell you that (theres about 2/3 of a bottle I'd say). I'm in Regina.
Cheers,
J