Apologies in advance for the tl;dr-ness!
Here's the scenario, first of all. I have a group of approximately-Napoleonic (fantasy setting ;-) ) soldiers, stuck on a smallish but inhabited island. Although the locals themselves have never bothered with black-powder weapons, there are a number of cannons left on the island from previous military occupations.
Quick note: both cannons are/will be garrison cannons: they're part of the island's defenses.
One of my characters is going to melt down some of these cannons, and (with the assistance of some of the locals) make them into a much bigger one, probably a 36-pounder. (I was toying with the idea of something like the Jaivana or the Tzar Cannon, but they're just too big.)
Here are the things I would like to check:
- Could a 36-pound cannon be made safely of bronze?
- There is a foundry on the island, left over from the previous occupying forces. Assuming it hasn't been looted or too badly damaged, would my character(s) need anything that wasn't already there to make the cannon?
- They don't have a hard-and-fast time limit for making this thing. I've found out almost nothing about how long it would take to make a cannon, except that a naval reconstruction group took 3 weeks to make a small one. They have about 2 1/2 years- would that be long enough to construct it?
- Lastly, how long would an average 36-pound cannon be? From this site, all I can deduce is "probably more than 8 feet long", but that's not very helpful...
Cannon #2 is something I'm a bit more worried about not getting right. It's a multiple shot cannon, similar to the Nagin Cannon (which I can only find mention of here, annoyingly): i.e. three smallish cannons connected together and firing simultaneously.
I can't really find much about old multi-barrel cannons- or indeed anything older than the Gatling- so here's what I'm trying to go for. Please tell me if this is implausable or stupid! It's essentially 3 cannons attached together, probably held together with some kind of metal bands, but I'm not sure what metal would work best. (Would they also need to be welded together?)
Also, are there any risks that this kind of cannon would have, that normal ones wouldn't? (More recoil when it fires? More likelihood of exploding? I don't know...)
Thanks in advance, and sorry for the barrage (heh) of questions!
ETA: The Ribauldequin seems like it might be a good starting point for cannon #2- anyone know anything about these? Wikipedia is lacking...