Mik,
For a nice machining project, a Herreshoff saluting cannon is a nice winter project. They are usually made from a piece of Naval Bronze (3-3.5" in diameter and 20-24" long. They are chambered for 10 gauge shot gun shells up to 4" in length. Talk about loud.
For those unfamiliar with the name, the Herreshoff family has run a SUPER high end yacht building business in Bristol, RI forever (think of the America’s Cup racing yachts for examples of what these folks build). Anyway, the great great grandfather of the current man running the company designed a brass signaling cannon to be bolted to the back handrail and fired off to warm off other boats in thick fog or an night - this was in the days way before GPS or even Loran C, radar, SW radios, and all the electronics boating fanatics today take for granted.
You can buy special 10g signaling shells from almost any boat dealer (they may to order them in for you). Signaling shells are blanks with only a tissue plug to hold in the powder and no projectiles. I can only imagine what kind of trouble you’d be in if you used a shell with a pellet load!
One of the great things about them is that they are NOT classified as either a cannon or a weapon - ATF recognizes them as a “signaling device”. As such they require no special permits to build, own or fire - at either the Federal or state level. A couple of years ago, I was using one at our July 4th BBQ and the local police showed up and confiscated it and threatened to arrest me. I went and spoke with Chief the next day - took the pertinent pages from the ATF and Federal Register and told him that if didn’t return my signaling device then and there that I would sue his police department, file a complaint with ATF and the FBI (the latter for abuse of police powers and corruption - i.e., the theft), and several other Federal and state agencies as they basically had stolen my $400 piece of bronze (I’m not kidding on the cost of the bronze rod here). Needless to say it was returned to me, albeit with a lot of grumbling.
Brian
Taxachusetts