Most of this series has lived on the bottom shelf. This set is the top shelf: the .38, .357, .40 and .44-caliber handgun rounds that sell by the case, plus the brand lines that compete inside the most popular of them. Familiar doesn't mean simple — nearly every cartridge here is a modification of another one on the same list.

Reading them as families rather than as a price list is the fastest way to understand what a box actually is.

The .38 family and its magnum

38 special cartridge arrived in 1898 as a lengthened .38 Long Colt and armed American police for most of the twentieth century. 357 ammo is that same case stretched again in 1935, loaded to far higher pressure and sized so it will not chamber in a .38 Special revolver — while a .38 Special drops into any .357 cylinder.

The .44 family and its magnum

44 special ammo for sale is Smith & Wesson's 1907 lengthening of the .44 Russian for its Triple Lock revolver. .44 mag ammo is that case stretched again in 1955, the round Elmer Keith spent a decade lobbying for and the Model 29 was built around — the same parent-and-magnum relationship as the .38s.

The autoloader rounds

380 bullets is Browning's 1908 pocket-pistol round, a step below 9mm in power and still the standard small-carry cartridge. 38 super rounds is Colt's 1929 hot-loaded .38 ACP, marked +P to keep it out of older pistols and later adopted by competition shooters. 40 ammo is the 1990 cartridge the FBI's 10mm experiment produced — a shortened 10mm that fit a 9mm-sized frame. 357 sig pistol ammo necked that .40 case down to a 9mm bullet in 1994 to reproduce .357 Magnum velocity in a service pistol.

Brand lines inside one cartridge

Within .38 Special, makers compete on purpose rather than caliber. 38 special hornady is Hornady's defensive line, built around a polymer-tipped 110-grain hollow point. 38 special wadcutters is a 148-grain flat-faced target bullet that cuts clean holes in paper — a load type older than most of the brands that make it.

What this tells a buyer

Four of these eight cartridges are lengthened versions of another. Knowing which fits in which gun — and which will not — is the whole game on this shelf.

Availability, pricing and shipping requirements for any cartridge listed above can change and vary by state. Confirm current stock, your state's age and identification requirements, and any local shipping restrictions before placing an order.