Ipeedin, that is a great looking cannon. After showing my 6 year old grandson both of your cannon threads, I could nor resist in modifying a 50 year inherited toy iron cannon that I got from my father. It was only bored in 2" and the fuse hole was 1/4" in deep on the 6" barrel. I re-bored the barrel to the fuse hole, added 15 grain of black powder with a tight paper wad and impressed my grandson with a lot of smoke and flash. My daughter would of killed us if she saw what we were doing.
The trunions were welded to the barrel. I am a little nervous about the recoil in shooting a .5" steel ball from this cannon.
Love it. Looks like you have the tools to build one from scratch - go for it.
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