I think Frank's got the formula, as well as the other fellas saying varmint bullets. I wouldn't spend money on pricey monos to go through. Lots of nice, "cheap" varmint bullets available for the .243. On edible game, I think there's nothing wrong with using a deer bullet for limited expansion, but for fur, why sew up an exit hole if you don't have to? Probably the monos wouldn't make a huge hole, but smashing a bone on the way out could get a little messier than you'd like.
Hit a coyote with my 6.5x55, and I had some 100 gr. hollow points factory ammo that I was burning for brass. I think the velocity is somewhere around 3200 fps, and the coyote was only about 90 yards I think. I got a good broadside shot at him, and kind of expected it was going to carry enough energy and enough bullet that it would rip him open. Must have puffed him up a bit if I could have seen it slow motion, but no exit hole.
Kind of the other end of the spectrum, albeit with a somewhat fragile big game bullet, I got one with my 45-70 and 325 gr. FTX factory loads once, and you could pretty much see all the organs in his body on the exit side.