If you use birdshot, or any target shot, the individual pellets don't have enough mass to really do anything, even at terminal velocity. Heck, Dick Cheney shot someone in the face at point blank range with it, and they we able to get on a podium and apologize to Cheney shortly afterwards.

Slugs are a different story. Not sure about larger buck shot, some of those can be as heavy as a pistol round, but not really aerodynamic.