(aka: ammunition)

Without ammo our guns would just be awkward clubs.

There are a whole lot of cartridges in existence. I shall mention a few of them that I actually like.
By the way, there is no one accepted standard method of naming cartridges. It's a conglomeration of old names that have stuck around, new names that were developed by folks trying to sell them, cartridges that were named after their inventor, and a whole lot of other things. Add in that some cartridges were named using the "traditional" English units of inches and such and that some of them were named using the metric system and things get even muddier than they already were. By the way, if you are interested in cartridges and their histories I cannot recommend too highly the fine book Cartridges of the World.

A brief word or two about the term "calibre" (or "caliber" -- either spelling is correct). The diameter of the projectile, expressed in hundredths of an inch, is referred to as that projectile's "calibre." The same word is also used to refer to the entire cartridge. Some "large caliber" rounds are actually fire smaller bullets than some of their "small-calibre" brethren but are so-called because they are more powerful. The actual name of a specific cartridge will often contain the word "calibre" as in the "Caliber .30 US Carbine." Often these dimensions are approximate at best. The .38 Special cartridge actually has a projectile that measures .357" in diameter. Historically there is a chain of events that explains why this is the case, but most of us just remember it as an odd fact. In fact manufacturers often fudge the numbers just to keep them different form their competitors' (or even their own) offerings. Thus we have the .218 Bee, the .219 Zipper, the .220 Swift, the .221 Fireball, the .222 Remington, the .223 Remington, the .224 Weatherby Magnum, and the .225 Winchester and they all shoot the exact same diameter bullets.

So let's start by making a list of some cartridges. Click on the cartridge name to go to the page where I talk about it.
The list is pretty much from smallest diameter bullet to the largest diameter slug.

    .22 rimfire
    .223 Remington (aka: 5.56 NATO)
    .30 US Carbine
    .30-30 (aka: .30 WCF)
    .308 Winchester (aka: 7.62 NATO)
    .300 Winchester Magnum
    7.63 Mauser (aka: .30 Mauser)
    7.92x57JS (aka: 8mm Mauser)
    9mm Parabellum
    9x23 Winchester
    .38 Special/.357 Magnum/.357 Maximum
    .38-40 (aka: .38 WCF)
    .40 S&W
    10mm Auto
    .45 ACP
    .45 Colt