.22 is more versatile for your use case. It hits harder and is better for small game, with plenty of ammo available. .177 shoots flatter and faster, making it better for pure target work, but it lacks the stopping power for humane kills on rabbits or squirrels. For a beginner who wants both, .22 is the practical choice.

I started with .177 because pellets were cheap and everywhere, and it taught me to read wind and holdover like a second language, but after taking my first rabbit with a .22 I never looked back because that extra diameter transfers energy so much better on fur and bone, and the trajectory difference at normal ranges under 50 yards is small enough that you can compensate with a decent scope and practice. The .177 gives you a flatter shot and more speed, which feels great on paper targets, but a .22 hits harder and bucks the brush better when you are sneaking through thick cover, and pellet availability is excellent for both so that is not the deciding factor. What really matters is your local laws because some places restrict .22 for small game and others encourage it, so check your regs first. I have used pinty devices for filling gear and they work fine, but the caliber debate is ancient and both will serve you well if you put in the trigger time. My honest advice is to buy a .22 for hunting and keep a .177 for plinking if you can afford a second barrel, because versatility is about having options, not choosing one perfect round.