Depends on how your hunting them.
If your going to sit out on a field edge or rabbit habitat at sunup take the 22. They do stay out and feed for an hour or two after sunrise and you can snipe them as they move around. Just sit still and quiet with your rifle.
If your going to push through thickets and flush them the rifle is useless. Take the 12 gauge. Ic choke and high brass 4 or 5 shot. They are f***ing fast when you bust one out of cover......have the gun ready all the time.....and for God sake.....SHOOT. I've taken many guys out for rabbit that literally watch them run away or "wait for it to get into an opening"....if the rabbit runs into cover keep shooting where they went into. High brass loads will get through brush surprisingly well. Basically if he's still moving your still shooting.
I hunt thickets with a shotgun as my preferred method. Got a few of them the last couple weekends. Even got my brother his first game hunting 2 Sunday's ago.....a nice cottontail that we flushed out for him.
As far as your "bite down on a pellet" concern.....I've been hunting and eating snow shoe hare and rabbit for many years......never bit down on a pellet. Rabbits are very thin skinned and lightly built creatures. The pellets don't tend to stay in the meat. When you clean the meat feel around any pellet holes for the rare occurrence one is still in there and dig it out. This is rare to find them anyway.
this was my brother's first hunting success couple weekends ago.
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