in the 1920s to 1940s there were a lot of octagon barreled .22s being made. See, it was cheaper to make them octagon than to make them perfectly round. we will need to know more about the gun before we can tell you how old it is. for starters, what kind of breech loader is it? Is it a hinge action single shot, lever action, falling block, trap door, pump action? a picture would be a great help, as would any numbers and words stamped on the gun
