Rate of fire can be limited by barrel overheating. If the barrel becomes too hot, there are variety of potential problems, including increased erosion (thus loss of accuracy over the long term) and self-ignition of propellant. Barrel liquid-cooling systems have been used with some rapid-fire twentieth-century naval guns. (Wu).
In 1820s and 1830s the French experimented with canon foudre (drum cannon), "equipped with a carousel of multiple powder chambers that could be pre-loaded." It was not a success; the seal between the chamber and the barrel was inadequate. (Mehl 36).
The logical solution was to use multiple barrels (i.e., a volley gun), rather than multiple chambers, as on the Swedish Nordenfelt 25 mm machine cannon (1877). It had a rate of fire of 120 rounds/minute, and an effective range of 1500 meters. This was a semi-automatic, gravity-fed weapon. (62).
On the Nordenfelt, the four barrels were fixed, horizontally parallel. Another approach was the Hotchkiss system revolving cannon; an 1896 Russian model fired 80 rounds/minute to 2700 meters. (63). Another source claimed that 12 aimed shots/minute at 4000 yards was possible. (Ireland1997, 42).
In the canonical Baltic War, the USE army had Requa-style volley guns. The USE navy wanted them for its timberclads, for suppressing cavalry raids on river shipping, but the army was given priority. (And fortunately, the air force conceded that it was "at least two generation of aircraft away from mounting machine guns.) (1634: TBW, Chap. 5). Ultimately, the USE navy went with a pivot-mounted Reffye-style mitrailleuse, having twenty.50 caliber barrels. Unlike the volley guns, these were fired in succession; maximum rate of fire was 60 aimed or 100 unaimed shots per minute. It had removable breechblocks and was loaded twenty rounds at a time. (1634: TBW, Chap. 41).
Grantville Firearms Roundtable, "How to build a Machine gun in 1634 with available technology: Two alternate views" (Grantville Gazette 4) may be of interest.
Whether at the breech or the muzzle, manual loading was the norm for big guns until the nineteenth century. When turrets were equipped with steam power for traversing the gun, thought was given to whether this same power could expedite the loading process. On Eads' USS Winnebago, steam power was used to lower the gun platform to a (safe) loading position (cityofart.net), but it didn't actually load the projectiles.
On the USS Indiana (BB1, 1895), the 13-inch gun turrets were semi-automatically loaded. They were equipped with hydraulically-powered ammunition hoists, the hoisted car having separate compartments for the powder and the projectile. However, in the magazine, these compartments were loaded by hand. A hydraulic rammer pushed the projectile into the gun breech. It's not clear to me how the projectile got from the hoist car to the rammer. (Fullam 187). A somewhat similar hatch loading system was used on the 16-inch rifled muzzle loaders of the HMS Inflexible (1895), but of course it communicated with the muzzle. (Ellacott 58).
In canon, Simpson's ironclads use salvaged mine hydraulics to open and close the gunports and perhaps operate the blowers that suck out the smoke, but it appears that the shell and powder hoists are operated manually. (1634: TBW Chap. 38).
This article continues in Part 2, "Ready, Aim, Fire!"
Notes From The Buffer Zone: Standing On The Shoulders of Giants
Written by Kristine Kathryn Rusch
I’m not sure what caused it: Maybe watching the news coming out of NASA about the Mars Rover. Maybe downloading too many Star Trek alert tones for my phone. Maybe the deep and somewhat excessive excitement I felt when I discovered some Stargate episodes that I missed.
I know something triggered it in combination with some historical fiction I’m planning. The key to historical fiction is to always make certain that your character is of her time. Maybe she doesn’t speak Chaucerian English, even though she lived in Chaucer’s time, but she has the right attitudes-attitudes she wouldn’t hold at any other time.
I know I am a child of my time. I tell my husband almost weekly that I was born into the 20th century for a reason. and that reason is really a handful of reasons, all intertwined-penicillin, indoor plumbing, and electricity. All those time travel romances in which the heroine happily decides to remain in 17th century Scotland? Well, either those heroines are crazy, the authors don’t know history, or (most likely) the books don’t speak to me.
What speaks to me-what has always spoken to me-is science fiction.
And the realization I had this past fall is that the reason I’m a science fiction writer is because I was born in the latter half of the 20th century.
I love mystery. I love romance. I love fantasy. Heck, I love good old complex family dramas without an ounce of adventure in them. I love great writing, great characters, great settings.
But I get truly passionate about science fiction, and that’s almost all science fiction.
Before I was old enough to separate reality from fiction (and yes, there is a difference, even to fiction writers), I saw science mixed with science fiction. My parents’ black-and-white television set brought me The Jetsons, Lost in Space, and good old Walter Cronkite interrupting this broadcast to let me know that mankind had orbited the Earth, had left Earth’s orbit, had died on the launch pad, had orbited the Moon.
Every kid in my school wanted to be an astronaut-at least until we heard about the amount of exercise those poor people went through-and all the girls had crushes on either Kirk or Spock. We almost came to blows at times, trying to decide which one we wanted to spend the rest of our lives with: the brainy one or the brawny one. Me, I rather prefer brains and passion to brains and bloodless, so I’ve always preferred Kirk.
Or maybe I just imprinted on all of those astronauts. It takes one supersized pair to climb into an Apollo capsule on top of a gigantic Roman candle, and let an explosion propel you out of Earth’s orbit.
How, after that, could anything I imagine even compare?
The first “book” I ever wrote was a typical girl-girl thing, featuring a pony. The second one had a car, I think, and the third-well, in the third, Captain Kirk goes back in time, lands in Superior, Wisconsin, and saves me from the drudgery that was my life. Romance novel meet Star Trek novel, twelve-year-old girl style. (We won’t discuss the Partridge Family gothic novel that followed.)
My friend Toni Rich and I spent most of our English class in our eighth grade year writing one of those back-and-forth novels-she’d write two pages, then I’d write two pages-and from what I remember about it (which isn’t much besides the colored paper), it was some space adventure thing with lots of hunky astronauts and big hairy monsters Threatening The Entire Universe! Yes, there were lots of exclamation points as well, and cliffhangers meant to stump the co-writer, not added for any logical reasons of their own.
But what if I had been born fifty years earlier? Would I have written so much science fiction? Or would I have written cozy mysteries after losing myself in the work of Agatha Christie? Would I write Gold Rush adventures because I loved Jack London? (I still do, by the way.) Would everything have snow and that horrible quest to build a fire?
Or would I have imprinted on the works of Herbert George Wells? Would I look to Mars and see possible invaders? Or would I rip off Jules Verne and writing diving stories set in the deep blue sea?
H.G. Wells makes me wonder if science fiction was just in the air. After all, he was born roughly 100 years before I was, and he became the prototypical science fiction writer. If a modern sf writer wants to do anything, she’ll have to climb on the shoulders of Wells to do it. His work examines both the possibilities of science and the failures of it, the politicization of science and how deeply personal it can be.