The first cannon I built was machined from a 3" dia. 24" long hollow 4340 compressor stud 1" bore. First test fire was 1-3/4 oz. ffg and a wadded up dry brown paper shop towel rammed down tight with a broomstick. All this transpired in our welding shop, at the urging of our Cajun machinist, with no carriage, I just sat it in a short wooden box backed up against the wall and aimed at the opposite cinder block wall across the shop. Closing all the doors, with the boss gone to lunch, we touched that baby off, 20+ years of welding dust and cobwebs came raining down for a good five minutes, and 1-3/4 oz. of ffg BP smoke inundated the shop. We, having not thought ahead, immediately switched on all the exhaust fans and opened all doors to air out the shop. We had just opened the big bay door and were discussing the test results and aftermath when a police car came idling down the street. Seeing us all out front he stopped to make inquiries. Yes sir, we did hear a rather loud boom. No sir, we are not sure where it came from, we were inside with the doors shut when we heard it. We came out to see if there was any smoke coming from the refinery (main gate 5 blocks down the street). Yes sir, you have a good day, sir. Upon further inspection of the crime scene, a perfectly round 1" diameter 1/4" deep indentation was found in the target wall

Even a lightweight dry paper wad is dangerous.

PS: Boudreaux started machining a cannon barrel from a scrap piece of stainless steel shaft during lunch break the next day.

My friend Lee built one that was about 3/4" diameter bore. He had made a carriage and it was a nice looking rig. One Saturday night we were all in downtown _____ hanging out at McDonalds when Lee rolled in with his cannon. He was wanting to shoot it and we encouraged him to do so. The cannon was loaded with a hefty charge of black powder, wadded with paper pounded on top of it. It was taken to a fairly empty parking lot and a lit cigarette was placed on the fuse. Then we drove up the street a little ways and parked where we could observe. After we had set there maybe 10 minutes a motorcycle cop drove by and just as he was past the cannon it went off.

This was on one of the main streets of the city and there were businesses up and down the street with large .. huge .. glass windows. We could see some of the windows buckling from the shock wave, though none broke. The motorcycle cop wobbled a bit on his bike but we were impressed that he kept it upright.

In a few moments police cars descended upon the parking lot where the cannon had been placed and the cannon was arrested. We stayed out of sight and after the police departed we decided we all would go home for the rest of the evening.

Nothing like cannon fire to set off a lot full of car alarms, or so I have heard.

I can smell the smoke.