Because I like all kinds of improvised cannons, this Wolf-gun has always been a favorite of mine.
Although the Long Cecil was larger, this one actually has a bit larger bore around 4.5 inches.
If you go to this page and scroll to about half-way the page you will find a photo of the gun, ammunition and people during the siege:
http://angloboerwarmuseum.com/Boer04_mysteries.htmlIt seems like they had for ammunition old round shells, solid shot and some 9 or 7pdr RML shells. There seems to be also a Krupp and Armstrong gun shell in the pile. I wonder how they loaded the smaller ca. 3" shells for rifled guns in a 4.5" smoothbore, if they actually used them.