[quote=MrFoxNews]
It doesn't matter how our weapons developed. It's a different world.
[/quote]

I believe it does matter. Technological development is a logical process, not a piecemeal collection of random advancements. Don't just slap some magical flintlock revolver rifles into your army because you think it's cool. There are people here who just don't seem to know how this kind of firearms technology worked, and that's not a statement against them--it just means someone should clarify so that things make sense and it's not some weird alternate universe of helicopters or whatever alongside muskets. 

Armored airships means that one of the first things to be developed in warfare would be a way to reliably pierce that armor repeatedly from long distances, unless you want every battle with airships to just be an aerial Battle of Hampton Roads where we just ping useless munitions off each other, or throw heavy rocks instead of dropping bombs. This is why one of the first things they did in aerial combat was to stick machine guns and autocannons on planes. The same goes for ship-based combat, where most ships were armed with autocannons rather than any giant guns. They're an easy and effective countermeasure, and logically they'd be one of the first things developed for that purpose.

For reference, this is a pretty standard Naval autocannon designed for anti-ship warfare. It would likely be pretty much necessary for any fights against dreadnoughts. This is around one quarter of the size of the main guns of the first dreadnought, conveniently named HMS Dreadnought.
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