One of the continuing problems I find in literature (and songs, TV shows and movies) is getting the nomenclature correct. And it's a big problem that doesn't seem to be getting any better. In fact it's chronic. For example, the creator of James Bond, Ian Fleming, was familiar with spying and knew some people actually involved in that trade. The irony is that he knew absolutely nothing about firearms. In his first stories, James Bond carried a Beretta .25 ACP, technically a pistol for a lady's purse. He upgraded Bond's firearm to the Walther, claiming it hit like a brick through a plate glass window. In truth, Bond would be better off with the brick. I carry pistols in the .32 and .380 family because they're easy to carry 24/7. So how do guys with a flare for writing pick good stuff? Trust me, video games are not a reliable source for information. I've never seen an AR-based rifle with a 203 attachment, and frankly, soldiers seldom do, either. In fact, it's old technology now. So, let me offer a solid example of making a good choice. Let's suppose you have a character in your book who must walk around in the seamier sides of life. No matter what his previous life (soldier, cop, unspoken) he has to carry often, he needs something that provides one-shot stops, he needs to purchase premium ammo or reliable handloads, and like most violent encounters, most happen after dark. Here's the firearm I picked for myself--the Smith & Wesson 360PD. (BTW, you'll laugh at how handloads are made. I start by going to an automotive shop that changes a lot of tires...) First off, this revolver is very light, sometimes too light with hard-kicking .357 magnum rounds. Yes, it's a magnum, but that caliber also fires .38 SPL rounds giving the owner great flexibility. The firearm is built from titanium and scandium, and while very strong it feels like a child's cap gun the first time you pick it up. It's built from Smith's tried and true J-frame, their smallest platform, but that's more than fifty years of yeoman service. Parts are everywhere and common. Speed loaders can be found at any hardware or sporting goods store. The 360PD has a neoprene boot grip to soften recoil. Since low light is often a problem in attacks, Smith has outfitted the revolver with their "Hi-Viz" front sight that gathers ambient light, and appears like a red dot to the shooter, but does not imprint a laser mark on the attacker. Over the last few months this revolver has been my constant companion when I wear a jacket. An Uncle Mike's #4 pocket holster/sleeve works in my biker pouch, or any deeper jacket pocket. And the smaller size allows me to carry 21 rounds of ammunition, two of those rounds are Speer 125 grain .357 Magnum Gold-Dot hollowpoints that I reserves for serious attacks--like those from a pit bull. (For size comparison, see the two longer cartridges in the lower picture. That rubber strip is called a 'speed strip,' and it allows the shooter to strip off one cartridge at a time to replace individual spent rounds without dumping out the entire cylinder. Insert the desired round, and yank off the strip.) I trust my life to this firearm. My point is that I assessed my defensive needs and chose a proper firearm. I think the characters in our stories should get the same privilege. Like any other important aspect of writing, this facet does require research. But even if you knew nothhing about revolvers, you could do a quick google of the 360PD. BTW, Smith & Wesson has a tremendous homepage. Lots of pictures, some with 360 views of their firearms. Use it as an asset.