Thanks for the input, guys. I actually have a hand forged spoon auger, about 5/8" in diameter. It is NOT easy to use. I will have to take some photos of it and also show it in action, as I have only idly played with it as of yet. According to Alex Bealer in Old Ways of Working Wood, the shell bit predated the spoon bit.
In fact, I have a decent selection of hand forged tools a craftsman in England made, including a froe, various types of chisels, and more. I will have to photograph them and put them up here. Some of them, including some Roman period draw knives, are really good tools that do what you want them to do. One day, I want to make a crossbow using 100% medieval technology and tools. It will be, I suspect, a real chore, but a lot of fun too.
PS engineer, I believe that augers were used by shipwrights and carpenters, so they must have been made in very large sizes. Betcha crossbow makers used them. Geezer probably has some insights, and I hope he chimes in.