The gun manufacturer/company name is Colt. The model is the Cobra, which is a 6-shot, aluminum-alloy-frame revolver. The caliber is .38 (shortened from the more complete name of ".38 Special").
Originally Posted by MichaelPureSoul
On a revolver of this type, the revolving cylinder is swung open on a pivot to load, unload, or check and see if it is loaded. It is a 6-shot revolver, so there are 6 holes in the cylinder (called chambers), one for each cartridge (or "round" of ammunition). If you pulled on the cylinder release lever, and then swung the cylinder open to check and see how it is loaded, you might see something like this:
The brass-colored cartridge casing was made by the Smith & Wesson company (S&W, who have made both guns AND ammunition in past years), and it has been fired (or "expended"), as indicated by the dimple in the center of the primer, located in the middle of the cartridge's base. The other 5 nickel-plated cartridges are labeled "Speer" (by the ammunition company of that name, now called CCI/Speer), and they have not been fired/expended, as indicated by the smooth, undimpled primers in the center of each cartridge's base. The color of the cartridge casings doesn't really mean anything in this example; I'm relatively sure that both companies have made cartridges in both plain brass and nickel-plated brass casings at some time during their production. These were just the examples I could find.
In this case, the photo is partially real and partially fake, as I had a .38 revolver in my safe, and a fired .38 caliber S&W-brand case in my fired brass box, but no Speer casings. So I searched online for a photo of a Speer-brand .38 case, and to my surprise, actually found one. Then I made 5 copies of it in a photo manipulation program, and transferred each of the copies over the empty chambers in a photo of my own .38 revolver (it's actually a S&W revolver, not a Colt, but that's difficult to know from the angle of the photo unless you're pretty knowledgeable about revolvers). The result is a pretty close copy of what the written description, above, is trying to illustrate with words.
"Placement is power" -- seen in an article by Stephen A. Camp
(RIP, Mr. Camp; you will be remembered, and missed)