I started reloading with shotgun shells in the 1960's and had access to trash dumps in Kansas where I shot several times per week. I've shot about every product, material and item on the planet with 12 gauge rounds and know what they'll do.
I have supreme confidence in 00 Buck loads and have loaded and fired cases of them. Birdshot, while absolutely fatal at very close range loses effectiveness so rapidly with distance, that it's a mistake to consider it for SD use. I've been shot several times with birdshot at 60-70 yards, it failed to penetrate my winter clothing and just plain made me mad!
I use 00 buck and slugs. That's the end of the tale for me.
You gotta die of something.....It may as well be something that you like!
Loving the Harley idle....potato, potato, potato.