Save the birdshot for the birds and use buckshot for the larger bucks invading your home!
The whole point of self-defense (SD) is to IMMEDIATELY stop the threat and a shallow wound from birdshot doesn't put as many odds in your favor as buckshot does! While still deadly at a slower pace, birdshot is more likely to leave the BG additional time to inflict harm (than buckshot). Use what you want for SD, as it's your life on the line. Most people want to put more odds in their favor and buckshot is more effective at preserving life than birdshot.
The whole point of self-defense (SD) is to IMMEDIATELY stop the threat and a shallow wound from birdshot doesn't put as many odds in your favor as buckshot does! While still deadly at a slower pace, birdshot is more likely to leave the BG additional time to inflict harm (than buckshot). Use what you want for SD, as it's your life on the line. Most people want to put more odds in their favor and buckshot is more effective at preserving life than birdshot.