How large of a cannon, a really small scale reproduction?
I didn't think that it could have any effect either.
But then the answers here led me to think about the model rockets with "rocket motors" that burn black powder for fuel.
Those things travel sky high.
Maybe a little reproduction cannon with an extra large flash hole and powder chamber could be moved a little.
If it were built out of aluminum or some other ultra-light alloy, and then the flash hole were placed right next to the ground, then who knows?
A person would need to be an engineer math wiz to try to figure it out.
Why not watch this to have some fun instead!
How to Shoot an Anvil 100 Feet in the Air - You Have Been Warned
https://www.youtube.com/watch?v=CHuQy0mqW5I