Borrowing things from the real world?

[Lord Ben]

Story is about a fantasy western (http://mythicscribes.com/forums/showcase/9632-montana-jackson-elven-city-gold.html)

Obviously there is no need to make a chair anything other than a chair or a longsword anything other than a longsword. But in a Western type genre a Colt or a Winchester, etc is a very different ballgame. "Monty pulled out his Winchester and rapidly worked the lever as he fired." or something. People reading the genre probably know what that represents when you say it same as "Igor drew his greatsword" tells the description of the weapon too. I don't think it'd be needed to invent entirely new weapons and companies but also don't really want to say "He pulled out his lever action rifle began firing" either as it seems a bit bland.

While I want to keep the story a bit pulpy and not diverge into world history too much I'd like it to make sense to the reader so it's helpful to have it straight in my own mind. I don't want to go with a straight up "set in the western USA circa 1870 USA with fantasy races" either.

Is there a preferred way?

 

[skip.knox]

I couldn't find a question in that post.

 

[Queshire]

Terry Pratchett uses coming up with his own company to great effect with the crossbows the watch uses in his city watch books. Um.... I don't remember exactly what the exact company is, but the parallel to something like a Colt or a Winchester is obvious.

 

[Lord Ben]

Like a Chesterwin rifle or a Bolt Warmaker pistol?

 

[Steerpike]

Made me think of this for some reason:

Romeo + Juliet Opening - Video Dailymotion

 

[CupofJoe]

Terry Pratchett uses coming up with his own company to great effect with the crossbows the watch uses in his city watch books. Um.... I don't remember exactly what the exact company is, but the parallel to something like a Colt or a Winchester is obvious.

Burleigh & Stronginthearm
As to the OP...
Unless it is important to the plot that it is a Winchester [Colt, Remington or a dozen others] because of something that only it does then I'd be tempted to call it a rifle or a Carbine. Most [well, at least some...] rifles in the old west were really pistol calibre carbines because they were easier to feed [and use on horse back].
When reading a story in a western setting I would hope most people have seen enough films to fill in any blanks you leave.
A Guy on horseback pulls out a gun and starts shooting fast - and I get an image of John Wayne as Rooster Cogburn charging across a glade at the Pepper Gang...

 

[Tirjasdyn]

There is no preferred way...just do whatever works for your story. Some of the tongue and cheek fantasy authors like Prachett and Anthony use puns and close-enough names. Others just work world history in as they see fit.