Latest "cannon" build is actually a Deck Gun From WWII. Mine is a non firing version of a cannon that was published in Model Craftsman magazine.
Issued in 1944 and 1945. I did see some copies of the article on the net a while back but can't seem to find the link at present.
The breech is of the interrupted thread type and operates as (or similar to) the original.
Barrel recoils (manual push to the rear and it returns via springs.
Manual Elevation and Manual training using the ball bearing base loaded with 3mm ball bearings.
Still need to make the elevation gearing.
I built a fixture for holding parts in alignment until they were soldered which aided the assembly process.
Assembly Fixture For Cannon or other Models
Here are the pics for all the parts and the finished gun: