I have had problems making clean kills with FMJs.
It all hinges on whether you want more one shot kills or less pelt damage. I have only taken Red Fox in Northern Baltimore County. I use .223Rem, surplus ammo, on which I have doctored the propellent load and OAL to suit my Tikka M595 Sporter. The rifle shoot ragged clovers off the bench at 200 yds. The foxes that I have hit have dropped, and the exit hole is no bigger then the entry hole.
North Texan, you did not mention which caliber you are using. It seems that the .223Rem is getting the job done for me, using fmj 55gr Surplus bullets.