# Ammunition Lingo/abbreviations



## Sha3488 (Dec 9, 2009)

Hi everyone and thanks in advance for your help. I'm new to handguns and am trying to soak up a lot of information. I own a S&W MP40, I've been buying American Eagle S&W 165 grain ammo for target practice, but I have alot of questions and cannot seem to find answers, so I turn to the experts (you) When buying Ammo what are the different abbreviations on the side mean? Example

165 Grain FMJ Ball?

180 Grain JHP?


what is the different between Centerfire ammo versus other ammo?

What makes a bullet Full metal jacket?

How many different types of ammo do they make for pistols?

Thank you so much!


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## Steve M1911A1 (Feb 6, 2008)

Sha3488 said:


> Hi everyone and thanks in advance for your help. I'm new to handguns and am trying to soak up a lot of information. I own a S&W MP40, I've been buying American Eagle S&W 165 grain ammo for target practice, but I have alot of questions and cannot seem to find answers, so I turn to the experts (you) When buying Ammo what are the different abbreviations on the side mean? Example
> 
> 165 Grain FMJ Ball?
> 
> ...


1. "165 grain FMJ Ball" = The bullet weighs 165 grains, it has a Full Metal Jacket (see below), and it may duplicate military load, which the military calls "Ball Ammunition" for archaic reasons.
2. "180 grain JHP" = The bullet weighs 180 grains and has a jacket (see below), but the jacket is interrupted at the bullet's nose by a cavity (a "Hollow Point") to help it expend when (or if) it hits something.
3. There are two basic kinds of metallic cartridges: centerfire and rimfire. In modern usage, a centerfire cartridge has a separately added, centrally-located primer, which is pressed into a pocket in the base of the cartridge's shell. It is visible and removable, and the cartridge case is probably reloadable. A rimfire cartridge has no separate primer, and its base is smooth. Its primer is injected into the rim of the case from the inside, before powder and bullet are added. A rimfire case is not reloadable. The centerfire cartridge is fired by a blow to the primer in the center of the case, while a rimfire cartridge is fired by a blow to its rim, its base's outer edge. (The words "shell" and "case" are interchangeable here. The artillery term-of-art "shell" means something else entirely.)
4. A Full Metal Jacket bullet ("Ball") is almost completely covered by an outer shell of a copper alloy of one kind or another. Its lead core usually shows through only at its base. It is not meant to expand. There are half-jacketed bullets, the rear halves of which are covered in copper alloy while the front halves are exposed lead. There are also Hollow-Point bullets (see above), and bullets made entirely of only lead.
5. There are, and have been, more different types of ammunition made for pistols than it is possible to recount here. Ammunition is classified by the bullet diameter (inch-fractions or millimeters), called "caliber," and by the kind of pistol for which it is primarily intended (which dictates case length and case-rim shape). Popular self-defense diameters include .38 (inch-fractions use decimal points), 9mm (metric designation, in millimeters), .40, and .45; while case-rim shapes include rimmed (primarily for revolvers), semi-rimmed, "rimless" (which has a rim, but of case diameter, occasioning a groove in the base of the case), and "rebated rimless" (the base is of smaller diameter than the rest of the case). The rim is the part of the shell that is gripped by the pistol's extractor, to get it removed after it has been fired.


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## Sha3488 (Dec 9, 2009)

Thank for so much steve, you have been so resourcefull


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## BATTLE 173rd (Dec 27, 2010)

*Hmmmbbbleeeee*

Great info. I love reading the wealth of knolwdge on this site...but "google" is not the best source of info, unless you know exactly what you are looking for. New ammo is developed, refined and marketed daily; along with new abbreviations. Insult free would be nice to see.


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## EliWolfe (Nov 20, 2010)

Steve M1911A1 said:


> 1. "165 grain FMJ Ball" = The bullet weighs 165 grains, it has a Full Metal Jacket (see below), and it may duplicate military load, which the military calls "Ball Ammunition" for archaic reasons.
> 2. "180 grain JHP" = The bullet weighs 180 grains and has a jacket (see below), but the jacket is interrupted at the bullet's nose by a cavity (a "Hollow Point") to help it expend when (or if) it hits something.
> 3. There are two basic kinds of metallic cartridges: centerfire and rimfire. In modern usage, a centerfire cartridge has a separately added, centrally-located primer, which is pressed into a pocket in the base of the cartridge's shell. It is visible and removable, and the cartridge case is probably reloadable. A rimfire cartridge has no separate primer, and its base is smooth. Its primer is injected into the rim of the case from the inside, before powder and bullet are added. A rimfire case is not reloadable. The centerfire cartridge is fired by a blow to the primer in the center of the case, while a rimfire cartridge is fired by a blow to its rim, its base's outer edge. (The words "shell" and "case" are interchangeable here. The artillery term-of-art "shell" means something else entirely.)
> 4. A Full Metal Jacket bullet ("Ball") is almost completely covered by an outer shell of a copper alloy of one kind or another. Its lead core usually shows through only at its base. It is not meant to expand. There are half-jacketed bullets, the rear halves of which are covered in copper alloy while the front halves are exposed lead. There are also Hollow-Point bullets (see above), and bullets made entirely of only lead.
> 5. There are, and have been, more different types of ammunition made for pistols than it is possible to recount here. Ammunition is classified by the bullet diameter (inch-fractions or millimeters), called "caliber," and by the kind of pistol for which it is primarily intended (which dictates case length and case-rim shape). Popular self-defense diameters include .38 (inch-fractions use decimal points), 9mm (metric designation, in millimeters), .40, and .45; while case-rim shapes include rimmed (primarily for revolvers), semi-rimmed, "rimless" (which has a rim, but of case diameter, occasioning a groove in the base of the case), and "rebated rimless" (the base is of smaller diameter than the rest of the case). The rim is the part of the shell that is gripped by the pistol's extractor, to get it removed after it has been fired.


Super post as usual Steve. Glad I DIDN'T try first!
Eli


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