Ini ‘Heart of Gold’, the minions rode horses and shot normal pistols nd rifles, while the rich leader had a laser pistol and a hover car with some large wapon mounted on the back. The whorehouse was wrapped in some kind of active solar sheathing that insulated the house while generating power.
So, exacly what you’d expect - a mix of old and new technology based on what makes sense for each use, and also based on who can afford to import the tech.
Lots of semi-autos…
Firearms of Firefly - pistols
Thanks, Ryan.
And you have solved one of the great arguments in Firefly!
It’s not like the 17th century settlers in the New World were living with the level of technology they enjoyed back in Spain and England. Nor could the western mining towns in the 19th Century maintain the same technology enjoyed by New Yorkers of the same period.
Pioneers, settlers and plain old rubes from the boonies always have lower tech than their big city counterparts. Even in those high tech areas, there was plenty of low tech still being used, in fact probably a majority.
It’s something I look for in sci-fi. If everything is shiny and new, it just isn’t realistic. Even in the 30th Century, people will still have hand me downs, heirlooms and antiques. And people in different areas or societies require a different amount and type of technology. Plus, architecture, infrastructure, and other technologies designed to last several human lifetimes.
Yeah, just look at all the wannabe Luddites on these boards, who apparently hook up to the internet via a coal fired modem!
We live in a world, right now, where more people have cell phones than have toilets. Technology is never distributed evenly.
They should make an app for that.
It’s not actually necessary that Vera require oxygen to fire. It need only be necessary for Jayne to think that that’s true. And let’s face it, he’s not exactly a chemistry whiz.
Simon is (at least to an extent), so he might know, but he doesn’t have any particular interest in firearms.
I have a better explanation: some weapons in the Firefly 'verse have ‘auto fire’, presumbly where the weapon has a computer that detects the enemy’s position, movement direction, wind speed, pressure, etc. It then solves for all this and fires when the computer indicates you are aiming in the right direction. This is mentioned in the episode where River guns down a bunch of bad guys without even looking, and Kaylee later describes what happened and says, ‘And it weren’t auto-fire!’
<geek mode off>
We actually have a sniper rifle like this today. You push a button when sighted on a target, which causes the gun to track. Then you pull the trigger - but the gun doesn’t fire until it determines that you are aiming in the right place. It’s very spooky, and even a novice can repeatedly hit targets at long range.
If ‘Vera’ has auto fire, then the simplest explanation is that exposing the weapon to vacuum screws up the sensors, preventing it from firing.
In fact, the real reason is that Whedon hired an ‘expert’ consultant, and the consultant told him incorrectly that guns need air to fire. And since this is Hollywood, no one on set had enough knowledge of guns to know this isn’t true, even though it’s fairly common knowledge among people with any experience with guns - or knowledge of chemistry.
*Hoban ‘Wash’ Washburne: Psychic, though? That sounds like something out of science fiction.
Zoë Washburne: You live in a spaceship, dear.
Hoban ‘Wash’ Washburne: So? *
And the Captain to be stupid enough to believe him. 
But let’s not get started on that again.
They seriously needed some stillsuits on that solar powered whorehouse planet.
The madam tells Mal that the wealthy villain and his henchman have plenty of money to build a modern city, but they like playing cowboy. So all the lowly peasants suffer.
Fine, I can accept the lower level of technology. But the FASHIONS? Seriously, why do people have to wear things that were fashionable during the old west?
Just don’t start wondering where all the Chinese people are. 
Yes, I found that to be objectionable. There should be some modern clothing.
I believe the cowboys clothes and black powder weapons to be due to primitive industry methods, black powder revolvers are easier to manufacture than a Glock, but there was too much cowboy shit.
Sure, there are some people who do. In some of the outer planets. But not everywhere, not everybody and it’s not the kind of people who Mal et co. hang around with, it’s the kind that would look at them like they crawled from under a rock (they may use their services but won’t invite them over to lunch with the wife). Back in, oh, the last 2500 years, the people in Cartago Nova, Londinium, Lima or Bombay who had access to stuff from the metropolis were the people who were in the highest social strata, often metropolitan themselves. Same thing.
I hadn’t heard of Firefly until I went to visit Doc. Surprised by my ignorance and delighted by the opportunity to share one of his favorite shows, out came the box and on the TV. By the second or third episode I said “ok, you said it was science fiction, but it isn’t really; it’s a western with spaceships. The Reavers are the indians” and proceeded to make some predictions for things that actually did happen at the end of the series.
We had great fun dissecting it. I guessed so many of the twists it was ridiculous, but even so they wouldn’t have been obvious to people who hadn’t spent as much time dissecting movies as Dad and I used to; a lot of them hadn’t been obvious to Doc and he’s no dummy. I found the story well-told and the universe internally consistant.
Define “modern”.
Have you not met any steampunks or old-school Goths?
And anyway, given the time difference, you should be just as upset at the t-shirts, sun dresses, cargo pants and Hawaiian shirts, they’re just as anachronistic (or not)