Seen it done, but wouldn't personally recommend it. Had a guy want to go out, he asked what he needed so I told him to get some #4 buckshot. He went to Wal-mart, and we were ready to roll the next morning. I should have known to check his gear, but he was supposed to be an experienced deer hunter. Of course he showed up in white tennis shoes, hint #1. Out we go. I called in a coyote, he let it get in to about 35 yards, and popped it. It dropped right there, but when I approached it, I noticed an odd pattern. He had gotten #4 birdshot and taken out the coyote with his 20 gauge. He did have an extra full choke, so the pattern was pretty tight, and the shot did go all the way through the coyote. But had I known what shells he had, I would have grabbed some buckshot from my stock.