I built a blunderbuss for a friend about thirty-five years ago, because he just had to have one. It was without a doubt the most worthless, dangerous, muzzleloader I ever built. It wasn't any good to hunt with, and was better at that than it was on the range. IMO, it was dangerous when being loaded because it was so short, and had such a massive bore. Even loading blanks for reenactments scared the devil out everyone around him because of the massive amount of powder it too to make it bang, instead of whoosh. JMO. I sure wouldn't build another one.
Hungry Horse