Hello everyone. At some point in the future I'm hoping to make my hometown's namesake, the USS Indianapolis. Until then, and as a way of getting an introduction into model ship combat, I'm looking to add some type of firing cannon for my HMS Beagle. But I need some help. Here's what I'm thinking about, but I'm open to whatever you all think would work. A single cannon, with a 1 to 1 1/2 inch long barrel, to sit up on the forecastle, able to fire 1 to 6 bbs (well more likely balls of flour or fish food pellets). There's a 4 x 4 inch area on the forecastle to mount the actual gun from. Directly below the deck there is a 2 inch tall area for stowing a CO2 canister and other components on the main deck. And if needed there's more room below the main deck inside the hull. So my question is, how would you go about making a single barrel, 1 to 6 shot bb gun, that would look like an actual cannon? Here is the link to my HMS Beagle build log if you want to take a look: www.andrewaasmith.com/HMSBeagle/Intro.php
Keep in mind that both Fast Gun and Big Gun style cannons are designed to launch round steel projectiles fast enough to penetrate thin sheets of balsa wood. They make certain assumptions about the material strength of the projectile. For example, a 6mm paintball would destroy itself if fired from a 1/4" Big Gun cannon, and I don't think a small lump of flour would fare much better in a Fast Gun cannon. So it would probably help to define your objective a little more clearly. How important is reloading capability? How important is the cannon's power? How important is the scale appearance of the cannon, and the smoke-and-flash effect from firing? It would be very easy to build a safe, compact single-shot cannon capable of firing almost anything, including flour, baby powder, fish food pellets, etc. You just need an air source (regulated CO2 or propel), an MAV-2 valve, a cannon, and an air line going from the MAV-2 valve to the back of the cannon. Load it up with flour or baby powder and you'll get a nice cloud of smoke when you fire. Simple, compact, and general-purpose, but not reloading and not powerful enough to penetrate balsa wood. If you want a reloading cannon that shoots bbs, then a fast-gun style cannon from Strike Models would do the trick just fine. A 16-gram CO2 cartridge is enough to completely fire a 50-round cannon, so ammunition and endurance would be good. If you go with a 1.5 to 2 inch barrel, you will lose a lot of hitting power, however. It will also be harder to conceal the brass 90* elbow fitting at the back end of the barrel, and you will not get any flash or smoke. There are other options, but I've gotta eat dinner now. I'll write up more afterwards.
Hey Kotori. To clarify, my objective is to be able to simulate the firing of a signal cannon from the forecastle of my Beagle, just for show. So I'm looking for simulated smoke and sound, not penetration or aiming ability. I'd like to be able to shoot at least a couple of times before having to sail her back to shore to re-load. The gang at R/C Groups who sail the big 1:24 frigates and brigs use some version of actual black powder with a igniter to make a miniature explosion. Kaboom! It looks awesome when it works, but it's one shot only and a tad on the dangerous side (but in a fun way no doubt). One combo idea I had was to somehow use the air flow to both shoot out a ball of flour and strike a cap-gun round. My larger objective is to get a little experience in dealing with the mechanics of a gun system for shooting projectiles with CO2, something I have zero experience with. (I shoot my RWS Diana air rifle for fun, but its pump powered).
Yeah, black powder could be dangerous, especially if you've got a reloading magazine for it. So let's review. You're looking for smoke effect and "bang" with at least some reloading capability, right? I believe it's possible to meet those goals using a modified "arizona" style cannon. Take a look here: http://www.queensown.org/armament/gun-construction.html you would replace the tube magazine with a medicine bottle or similar, filled with flour or baby powder, and increase the angle of the final piece of magazine tubing so it should be able to gravity feed. Note that this cannon is kinda tall, so it might not fit into the fo'c'sle area. I don't know for certain how much of a smoke cloud this would make, but it would certainly make a nice bang, and it would be reloading. Another possibility that might work is to use the Arizona cannon base (accumulator plus MJV-2 valve), with a medicine bottle in place of the T-shaped breech mechanism. The wave of air pressure would pick up some flour from the medicine bottle, then go up, around the bend, and out the barrel. Again it would be height-intensive, but it has good potential. I may even be able to test this one. I've got a few spare MJV-2 valves, and a few spare short-length barrels. All I need is a medicine bottle, some super glue, and a drill and we'll know how well it works.
Kotori There's a ship called the Lady Love http://bellsouthpwp.net/c/h/chrisgski/page16.htm that might have something like what I'm looking for. Here is how the builder describes it: "Cannons equipment is installed. After small explosion, I upgraded the plastic lines to thicker rubber lines. The mav-2 valves are from www.Swampworks.com. I later then added the talcum powder kegs between the valves and the cannons, for an awesome visual display." Do you recognize this setup?
