Training an Adopted Beagle for Recall/Running Rabbits

Hey all! I was lucky enough to rescue a handsome ten month old beagle off craigslist two weeks ago. He's my first beagle, and the first dog of my own I've owned. He's already housebroken (awesome for me) with only a few accidents that boil down to me not reading the signs he was giving me. Otherwise, he's pretty stubborn and barely trained in obedience, though that's going well with a ton of treats.

I'd like to be able to take him out in the open off leash someday, and it would be great to get any advice I can on training recall. That's his weakest point in training right now, and to me, it's the most important.

Otherwise, having this guy just for two weeks has made it incredibly obvious that he needs a job. A huge part of me wants to take him out to chase some rabbits, but I have zero experience there - the only wild animals I bring home for dinner are fish. But now I have a young beagle itching to track anything he can, and a pellet gun that'll get the job done... any advice on that front?

(Here's Luke at the dog park. He was a little overweight and clearly hadn't gotten out much when I took him home, but we're working on it)