Ready, Aim, Fire

October 26, 2012 2:47 PM

Let's say you have a miniature ironsides cannon, about the size of a medium terrier and quite heavy, capable of firing. Let's say it looked something like the second cannon from the top here. Let's say you were setting this cannon off to celebrate the Fourth of July or something and just wanted a big boom. What would you load the cannon with, and how would you load it?

Further, would it be possible for the cannon to fire off things that exploded in the air, particularly for show? What would happen if someone were accidentally hit, at close range, by cannonfire from this petite cannon? How dangerous would that be? I remember seeing a video of a little palm-sized cannon that fired off little palm-sized cannonballs with enough force to lodge them in stout walls. So it seems like a cannon of this size and heft has the potential to be lethal?

FYI: Do not actually own said cannon. Am not planning on firing any cannons near any people anytime soon.

Thanks, MetaFilter!

posted by Miss T.Horn to technology (10 answers total)

Loading the cannon with a projectile would be very dangerous. Seriously, seriously inadvisable. Do not do that. Salute cannons are generally designed to be loaded with a small charge of black powder only, or sometimes a carbide-based product ("Bangsite") if it has a spark plug fitting in the back. They're not designed to actually shoot anything, and are frequently made from cast metal that will explode if you try.*

Anyway, you can't get actual (real) black powder anymore. (The last factory making it in the US blew up in the 70s, IIRC.) But you can get synthetic black powder in any good gun shop; the most common brand is "Pyrodex." It produces the same pressures and is usable in black powder arms, including salute guns. It comes in pellets and then in various grades of actual powder; I'd get the actual powder in middle-fineness grade like FFg. If you can locate the brand on the cannon, you might be able to find a manufacturer's recommendation of powder grade, but I would err on the side of less fine if in doubt. More fineness means higher pressures and more of a "bang", but you really don't want to overdo it.

There's a video on how to load and fire one here.

* I have a certain amount of firsthand knowledge in this, due to a misspent youth. Although I still have all my eyes and fingers, I'm probably lucky in that regard.
posted by Kadin2048 at 3:04 PM on October 26, 2012 [1 favorite]

Anyway, you can't get actual (real) black powder anymore. (The last factory making it in the US blew up in the 70s, IIRC.)

Ah! I should have clarified. I'm writing about how this would have been done in the 1950s. So black powder would definitely have been in use then, and available?
posted by Miss T.Horn at 3:07 PM on October 26, 2012

Miss T.Horn writes "So it seems like a cannon of this size and heft has the potential to be lethal?"

Easily. Consider that all black powder pistol is is a very miniature cannon and those are lethal.

Also consider that people have been killed by thrown baseballs. It's important never to aim signal weapons in the direction of people.

Finally black powder is buck simple to manufacture (the only stumbling block is preparation of the charcoal); lack of a commercial source isn't much of an impediment to firing such a weapon on an occasional basis. In fact by adulterating the black powder mix or using less than perfect black powder mixtures in home made black powder you can get more smoke/flame/sparks and generally make the firing more impressive than a perfect mixture.
posted by Mitheral at 3:28 PM on October 26, 2012

I would contact a local Civil War or Rev War reenacting group. They have connections with artillery groups that can give you an idea what to use and how much.
posted by PJMoore at 4:01 PM on October 26, 2012 [1 favorite]

Look for the video of the Mythbusters cannon accident. It wasn't a particularly large ball or cannon, and the damn thing went through walls after flying a quarter mile (or something like that).

Think of dropping a bowling ball on your foot. Only denser and faster. Definitely dangerous. If someone were to shoot one off for celebratory purposes, chances are very good they just packed the powder down and maybe used some wadding.
posted by gjc at 4:41 PM on October 26, 2012 [1 favorite]

You sure can get black powder. F - FFFFg, Pyrodex equivalents, and everything in between. Check any quality black powder hunting site for prices and shipping. In the US, http://www.goexpowder.com/ is the main manufacturer of black powder. People using black powder arms for hunting, sport, etc. generally use the modern equivalents because they're just a bit better.

Manufacturing black powder is not as efficient as ordering it online.

However, if what you are talking about is an actual "salute cannon" from the 50's, many were set up to fire blanks, often 10ga shotgun blanks. In that case, googling any of the maker's marks should set you right with what is needed to make it work. Getting the needed supplies in the 2010's may be a challenge.
posted by graftole at 6:41 PM on October 26, 2012

Also historically: With a miniature/salute cannon, you'd not usually have a shell that explodes in any way shot out of that device by the man-in-the-street. Unless it is a firework (and not a cast-iron miniature cannon), the NFA of 1934 might regulate that projectile.

If it is a firework, like the mortars that pyrotechnicians use to launch all those awesome starburst shells, that's a different story with different fed and state regulations.
posted by graftole at 6:51 PM on October 26, 2012

for projectiles in the 50's they would prob just use rockets like today. For show, though, they might add a bit of aluminum powder or 'flash powder' too...that's what makes the bright white 'flash' and really loud 'bang' in fireworks...though it's pretty dangerous...but, hey it was the 50's right? probably also some other 'pyrotechnic composition' for sparkles...IIRC, i have seen one of these fired in a historical picture (though i can't remember which) and it DEFINITELY seemed to be a combination of all of these: BOOM, BANG, FLASH, SMOKE, SPARKLE. (and the sparkles made that delightful sizzly sound) These cannons are designed to be showy...and LOUD. (hmmmm...it might have been an '1812 overture' being performed outdoors scene...)

also, yeah, put a metal ball in it and it will totally kill someone...it's basically a massive rifle. that's why you wouldn't put a 'thing' in it, like a firework...it would just explode. (possibly also the cannon!).
also, projectile fireworks shot any direction but straight up (to then disintegrate) are kind of a Bad Idea.

so: probable ingredients: black powder, sparkle powder, maybe flash powder (but that might actually burn hot enough to harm the cannon itself)
posted by sexyrobot at 11:05 PM on October 26, 2012 [1 favorite]

So I umm happen to have some umm experience with this as well. What we always ended up doing was loading it with pyrodex, and as a shot we just used a little bit of aluminum foil wadded up so we could tamp everything down. That way the thing you end up firing doesn't usually go that far and also isn't dense or heavy. I still wouldn't stand in front of it, but you dont need to worry about having a three mile range cleared ahead of time. Ours was much smaller probably an inch in diameter barrel and we loaded it with 200 grains of pyrodex. The foil would be nothing more than a piece like 2 in by 2 in square wadded and pushed into cover the powder. Stood well behind and lit the fuse and ran like hell. Our foil only went like 10 yards and also tended to open up and slow down very fast.
posted by koolkat at 10:16 AM on October 27, 2012

Most of those little salute guns are 68-70 caliber (or so, the tolerances aren't very tight). You can definitely ram a musketball down one and fire it, with some cloth wadding, and it would absolutely be fatal if it hit someone.

At short distances they are surprisingly accurate.

The last black powder plant in the US was located somewhere in Indiana and run by Olin Matheson Corp.; it suffered a bad explosion sometime in the early 70s (IIRC) and was never rebuilt. I think it was just producing black powder for limited military applications at the time (the igniter bags/patches used to set off the main charge for big naval guns and some field artillery pieces). Pretty much anything manufactured after that (unless it's new-old-stock) is synthetic black powder substitute. I'm not entirely sure when Pyrodex came on the market for sporting/civilian purposes, but I think it displaced real black powder fairly quickly as it's a lot less hydroscopic and thus more reliable.

However, in the 50s real black powder would have been widely available. You could get it in any gun store, and probably even most rural hardware stores. Except as an experiment (not too uncommon; I think every kid tries this at some point, or used to before chemistry sets got lame), there wouldn't have been much reason to create black powder from charcoal and potassium nitrate.
posted by Kadin2048 at 1:42 PM on October 27, 2012