A blunt is merely a halfted scraper. Someone started a rumor at some point that these were used to just stun a prey. Not to many subscribe to that line of thought that I know of.
Look how large the blunt is, goes all the way across four fingers. Look at the size of the part to be hafted, it's way to large for an arrow shaft. Peers to me it would be a scraper either hafted or used without a handle. Putting that on an arrow would require a shaft just about the size of a broom handle.