Now, with the way overly ambitious plans about group cosplay that gave birth to an idea of making their character's weapons for my friends birthdays I have set to make most complicated prop so far - a revolver from Dan Abnett's novel "Pariah". Description from a book:

…It was a huge, chromed thing, a revolver with two barrels, one of a regular size and the second of greater bore beneath it. It was an old, Guard-issue weapon, a Lammark Combination Thousander, a weapon for an officer, or for use in trench-war and street fighting… The Lammark’s centre chamber was a large-capacity slot for a buckshot cartridge or a breaching round….

So, two barrels, center one using shotgun rounds... Wait, I know what that is - it is LeMat revolver, iconic on it's own as a representative of those real world weapons that would fit perfectly in wacky "steampunk" setting. I mean, look at that thing:


So, The Inspiration is chosen, it is gonna be easy.
Not.
Now, Mr.Abnett noted that a gun was chromed, but I have personal problem with too shiny chromed guns (It is not a weapon, it is a pimp's accessoar), so decided on different color.

Wait, aren't you getting a little ahead of yourself, talking about a color prop would be painted before you even started working on it? Well, yes, but I am also trying to describe my thought process, so some jumping forward and backward are in order.
OK, so let's start making it, again.

This was the earliest WiP photo I could find - it shows size of it compared to Rogue Trader's guns that look tiny next to it and shows how some things were made - frame from a thick plasticard (IIRC two 8mm panels glued together), central barre from a plastic tube, upper barrel from an aluminium tube, grip from a layers of soft wood glued together and then sanded to the shape and grip bottom cup from a cabinet handle.
Chambers in the cylinder were more plastic tubes glued around central tube.




Next pic shows more progress and retro-futuristic design choices - ventilated rib on the top of the barrel, fluorescent plastic front sight, and a brass rear sigth, brass screws, basic hammer shape and a fancy trigger guard.
I have also planned to make an ammo belt and a holster for it, alas it was not to be, but a shotgun shells were later recycled for a shotgun.



Then it came my favorite part - decoration. Brass sheets covered part of the plastic to give an illusion of the brass frame, cylinder was improved to look less like a random collection of the plastic tubing and more like a real thing, grip decoration and lanyard loop were added, hammer was finished and front sight got a little protective wings. Some Warhammer and Warhammer 40k plastic bitz were finishing touches

.




Then it was a painting time - dark green finish, brass details and ivory like grip worked well enough to bring it to a life:




All in all, really fun project with one major but - it took ages to do it. Why and how, when you said you did derringer in a few hours? Well, cause revolvers are damn complicated - fitting cylinder in the frame, fitting barrel to look aligned with cylinder, making grip angle work with a trigger so a prop would actually fit in the hand - it all makes for a lot of work, but don't despair - that work will make a prop more awesome in the end.

http://bubbaworkshop.althemy.com/viewphotos?albumid=1126