a 20 ga with 6 shot is as big as you would ever need any bigger and there is not much left of the rabbit. e collar to help you when they show interest in deer or anything else you don't want them on. biggest thing is to give your dog ample opportunity on rabbits and natural ability will come out .22 is really only good for hunting rabbits without a dog. with a dog your not gonna get very many standing shot. good luck and you should do just fine. be carefull around roads. try to hunt as far off of roads as you can because if the rabbit crosses the road your dog is going across too.