It's funny, but E-Bay has a NO GUN or anything that shoots policy. You'll often see locks, stocks, and barrels each sold separately to comply with that rule, but then there are black powder cannon. Although most are small scale and in the rifle/pistol caliber you'll frequently find a copy of a famous barrel to a full carriage with limber and it might go to .75 caliber. A lot are .50's. And then you have the large bore noise makers of golf ball, tennis ball, soda can sized bores. To make them legal on E-Bay a word of caution is given stating that the gun is for signaling purposes only and cannot fire, nor be made to fire a projectile. Hogwash!! Any barrel with a fuse hole, some powder and fuse and an appropriate sized ball, can and will fire if it's lit. I was fortunate to win the bids on two such noise making devices that look like some I'd seen at cannon company sites. They're multiple fire units with two to as much as five bores with as many fuse holes so you have to tie your fuses together to get them to sequentially fire. The problem with the one's I've seen is that they are made of aluminum. Not my considered best material.
Well the ones I got (both made by the same manufacturer) are CNC milled out of a solid block of stainless steel and weigh a considerable amount for their 1" X 3" long bores. I have a two shot and a three shot. I also have a BNA Bircher golf ball mortar that's a copy of some famous mortar scaled down to golf ball size. Some folk on E-Bay make their noise makers by welding a base plate to steel tubing, drilling in a fuse hole and calling it good.
I found a maker of those that at least used 1/2" or thicker walled tubing on a stainless base plate. I asked him if he could make a golf ball cannon barrel out of stainless and made to fire vertically like a thunder mug. It's 3.75 inches at the breech and 2.5 at the muzzle of it's 11" length. This was machined out of solid stainless rod. He indicated that for that size he would machine a breech plug with a chamber divot, thread it into matching barrel threads and then weld and mill the bottom flat. He also put two blind 5/16 X 18 holes in the bottom for mounting purposes. The barrel has a continuous taper from breech to muzzle where material was saved to put a ring around the muzzle like you'd see on most cannon. Now does that sound like a common or practical way to do the breech of a cannon that size? Keeping in mind that I am not firing anything including golf balls (it's aimed straight up and I don't like to run). So I'll just be using a suggested charge of loose black powder, packed slightly and a cardboard over-powder disk for blank firing.
All these devices are to be mounted on a common mortar bed and situated so that I can fuse them up to fire the 5 1"ers then the BNA mortar and finally the 11" cannon barrel/thunder mug. Should make for a fun forth of July next year or sooner if I could find a place to let her rip. Back to my question though, what are other ways to deal with a breech for a cannon this size and to do it safely? Smithy.
