not golf ball sized but 50 cal round ball cannon's at williams arms
You might find some heavy wall DOM tube that is a close fit, from there you could weld one up, depending on what kind of external profile you had in mind. A piece of tapered steel octagonal lamp post might make an interesting profile, 2" plain steel towball for the breech end, a couple of chunks of shaft about 2" for the trunnions etc. etc. Fill the space with concrete and weld the muzzle on!
and they are probably being very prudent to do so, I have built several cannons from 50 cal to 2.625 bore (pop cans) and the first thing I would say to a new cannoneer is that loading & shooting a cannon sized charge and an ordinary muzzle loader is a completely different ball game...I thought i had a good handle on BP shooting until I built my first 1.625 bore cannon.none of them want to get into the legality of making anything cannon like. Afraid of being sued if it explodes.
....disregard the previous post about using a 2" ball hitch as a breech plug, I would consider that completely inadequate unless it has a proper breach plug cross drilled & double welded backing it up...in other words ditch the hitch!!
Didn't one of the OIC's ban anything 50 calibre and larger, and over some number of joules?
It's possible that what you are looking for is now prohibited.
Yes, but has slowed down a bit, due to some health issues.Brasswithclass still around?