I needed a cannon to take to my sisters for the fourth of July. I decided on the following design requirements:
It had to shoot firecrackers
It had to be sturdy and not too small.
It had to be safe to use around the mess of kids that always show up, and they had to be able to help without too much danger.
It had to be built in one day, “cause it was the night of the 2nd.
The following is what I came up with. I started with a piece of 1¼ 360 brass drop about 3” long, faced it , bored it, turned off the rough surface, turned it around, sawed it to length with a hack saw, and cut the breech end sorta half round freehand by using a bit in a straight Armstrong holder like a gouge on a wood lathe. That actually worked quite well as long as the rest was very close to the work. Stuck it in the mill and cut a half round groove for the trunnion. Turned the trunnion to fit the groove and soft-soldered it together. No touch hole was drilled.
A block of wood was clamped in the milling vice and the top was cut so the side profile was what I wanted then the waste was milled out from between the cheeks, the bed and cheeks are all one piece. I added a couple of cross pieces and a handful of brass rivets drilled and glued in.
I cut a .22 empty to ¼ inch over all and soldered a brass rod to it for a powder measure. I transferred powder from the can, the can of 4F was left locked in the truck, to a plastic film can about ½ to ¾ full so if there were any accidents there wouldn't be a big explosion.
To load it the “help” would get a scoop of powder from the film can, which I pretty much kept an eye on, closed the lid (that was a rule), then poured it down the bore. Then the fuse of the firecracker was folded up the side of the firecracker and pushed down on top of the powder. The fuse was lit and the cannon would go off and the firecracker would pop about 15 to 20 feet in the air.
No touch hole meant no fuse parts spitting at the kids, they all come out the “business” end, and firing it at 45 degrees meant it would be hard to hit anybody. The kids quickly found out that overloading it gave LESS noise and height so settled on loading it with one scoop. It was originally drilled for 1” firecrackers as that’s what I had laying around, I may drill it a bit deeper so 1 ½ firecrackers will work a better.
The bottom edge of the sled is about 4.5" long. The bore was drilled with a 17/64 bit, .7" deep, could be deeper for 1 1/2 in crackers. You want 1/8" or so of fuse sticking out of the muzzle. This makes the walls a bit over 2 bore diameters and much thicker at the breech, safe enough I expect.
Side view with powder can:
The business end:
Finally "smoke and fire":
It is not very loud, the firecracker makes much more noise, but it is very fun. I hope this was at least worth the time it took for you to download it anyway.
Thanks,
MikeR C
