I still need a fair bit of practice with mine!
To be fair mate i have missed a lot more than i have hit, and nearly everything has been in cover, or just not been expecting it. Squirrels, rabbits, rats, and various things with feathers. Pheasants are easiest obviously, sometimes you get three shots at the same bird
Edited to add - take it out lamping and try to knock over a couple of squatters. If you miss and they run you can always then slip the dog.