So I just finished a good sci-fi book (Footfall, by Niven and Pournelle).
Earth is invaded by small elephant-like aliens who, after being nuked out of Kansas, land in Africa.
At some point, the U.S. President has a talk with a (drunk) sci-fi writer who works in a "Threat Team" and it goes like:
"There's plenty we can do./ ...... / Who makes elephant guns?"
"There are people I can ask," said the President. "The British? They made a big double-barreled rifle, a 'Nitro Express'-"
"Round up all you can find," Reynolds said. "Send 'em to Africa. Somebody there can use them," he laughed. "It worries me to excess, there may be a young Zulu warrior somewhere who doesn't have an elephant gun."
[Yeah, call Chapuis, Purdey and Rigby and have 50000 guns shipped with a million rounds to the guerrilla... ] (That's me grumbling...)
It turns out that the Zulu kill the aliens very dead with spears, and the aliens can't manage to throw the spears themselves, without propulsion or guidance system, "with that little shovel like device at the front..." .
I also remember choking in one of the otherwise excellent 'March' book series, by Weber and Ringo.
The heroes have to equip natives of a less advanced planet with blackpowder guns. As brass extrusion would take too much development time, they settle for paper cartridges.
They come up with a cap-n-ball cavalry revolver, 'Dragoon like but with a swing out cylinder for faster reload', and an infantry rifle whose cartridge incorporates a thick gasket wad at the back , 'the next bullet pushing the wad out of the barrel upon firing' .
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