Congratulations on The .221 FB. What model did you settle on? Do you intend to reload this cartridge? If you like this round you may find the Remington 17 Fireball to fit a nitch as well.

I have been just getting into this round for a little over a year now. Can’t share much in the way of experience taking fur or critters. Just have not found myself with much in the way of opportunities yet. Yes I have taken a few bunnies and Prairie dogs, though I am looking forward to opportunities on coyotes and bobcats. Have to expect that both the .221 and the 17 FB will make a great calling round.
I have been reloading this round from the start of my .221 experiences. Thiscartridgesurprised me with the accuracy and velocity achieved with a variety of bullets and a small charge of propellant. I have had excellent luck with 35 grain V-maxes up to 55 grain SP's. BR4's have been my go to primer and Lil-gun and H4198 have been the favored powders for me.
This round should do well for you inside of 200 yards. Though it may surprise you out to distances of 300 yards or so. Can’t help but say, I have been pleased with my 55-grain SP loads out to 300 yards.

This could be a tough time to get into reloading this .221 FB cartridge, as brass can be tough to get. The 17-fireball has dried up the supply of .221 FB brass to one degree or another for the last 9 months or so. Hopefully the brass supply issues will work themselves out over the coming year.