Every new shooter faces challenge of buying ammunition. While your first visit to the gun shop or the big box sporting goods store, you might get the sales person to select some ammunition for you, eventually you will need to select your box of ammo on your own. The challenge is that selecting ammo involves making a number of decisions and understanding a universe of strange acronyms and terminology.
While the decisions can seem simple, often there is unseen complexity based on the long and varied history of firearms. There are firearm models and even original rifles, shotguns and revolvers that are still in common use 146 years after their introduction. This means you may find a box of ammunition designed for a 146 year old firearms sitting next to one designed in the last decade and ammunition reflecting all the changes that have occurred over that 146 years.
The most important decision is to select the correct caliber for your firearm. Seems simple enough, especially if you have selected a common caliber such as 9mm. So you go the wall of ammo in your preferred firearms purveyor and you look for 9mm and find the section with 9mm ammo.
There you might find some combination of boxes labeled with the following calibers:
- 9mm Luger
- 9mm Parabellum
- 9x19mm
- 9mm NATO
- 9mm Short
- 9mm Browning,
- 9mm Kurz
- 9×17mm
- 9×18mm Makarov
- 9×23mm Largo
- 9×23mm Winchester
- 9×23mm Steyr
- 9 mm IMI
- 9x21mm
Which box is the correct one? The first thing to understand is that it is not uncommon for a single caliber to have multiple designations. Because of its wide spread use and long history, 9mm might be an extreme case. In fact there are really only 7 calibers not 14. Some of the 9mm calibers have multiple names.
- 9mm Luger, 9mm Parabellum, 9mm NATO, 9x19mm
- 9mm Short, 9mm Browning, 9mm Kurz, 9×17mm
- 9×18mm Macaroon
- 9×23mm Largo
- 9×23mm Winchester
- 9×23mm Steyr
- 9 mm IMI, 9x21mm
So your first challenge is to know the caliber you need as well as the alternative names it may have. The second important decision is to decide what bullet weight you want. Bullet weight is listed in grains, where there 7000 grains to a pound (437.5 grains to an ounce). Bullet weight can effect the energy delivered to the target, the recoil when fired, and even the velocity the bullet.
The 9mm Luger, which is what is commonly meant when someone talks about a 9mm pistol, has three common bullet weights: 115 grains, 124 grains, and 147 grains. 115 grains is the most common weight, 124 grains is the standard weight for 9mm NATO and 147 grains is subsonic, which makes it the preferred ammo for pistols using silencers.
After selecting a bullet weight, the next choice is what bullet type you would like. There are a multitude of bullet types and more being developed everyday. Even more confusing, bullet types are usually indicated by acronyms.
- FMJ – Full Metal Jacket – Lead core covered by a copper/brass metal jacket
- TMJ – Total Mental Jacket – Same as FMJ except includes base of bullet
- CMJ – Complete Metal Jacket – Same as TMJ
- FMC – Full Metal Case – Same as TMJ
- HP – Hollow Point – Hole in front of bullet that aids expansion.
- JHP – Jacketed Hollow Point
- BT – Boat Tail – A tapered base, often used on rifle bullets to reduce drag from long range high performance rounds
- BTM – Boat Tail Match – Boat Tail bullet designed for shooting matches through precision manufacture
- RN – Round Nose
- LRN – Lead Round Nose
- FP – Flat Point
- RNFP – Round Nose Flat Point
- TC – Truncated Cone – Similar to RNFP, basically a round nose bullet with part of the point cut off.
- TCMJ – Truncated Cone Metal Jacket
- SP – Soft Point – Bullet made with a soft lead alloy which allows to to expand. Often used in hunting
- PSP – Pointed Soft-Point
- JSP – Jacketed Soft-Point
- WC – Wad Cutter – A target bullet designed to cut large holes in targets bu using a cylinder design within point
- SWC – Semi Wad Cutter – a truncated conical nose, designed for feeding in firearms the have issues with wad cutters such as most semi-automatic pistols
- LSWC – Lead Semi-Wadcutter
- SJ – Semi-Jacketed
- SJHP – Semi-Jacketed Hollow Point
- BJHP – Brass Jacketed Hollow Point
- HC – Hard Cast – Hard lead alloy used for hard targets such as large game animals (elk, grizzlies, etc.)
The final choice that can be made when selecting ammunition is selecting standard or over pressure rounds. Over pressure rounds are indicated by +P or +P+ on the package. Since over pressure rounds rounds exceed the maximum pressure specified by SAMMI standards, it is important to make sure your firearm is rated for +P or +P+ ammunition. Look for +P stamped next to the caliber not the firearm.
Hopefully, now you have an idea of what you may be buying the next time you face a wall of ammo boxes.