Acronyms are everywhere in the gun and ammunition industry, and when reading through descriptions, it is enormously helpful to know just what those acronyms stand for. We frequently get questions from customers regarding various bullet types in both handgun and rifle cartridges. It’s easy to see why: there are numerous terms and acronyms used to describe the bullets.
Let’s briefly go over the basic types of bullets that can be found on the market today.
Common Bullet Types
- FMJ (Full Metal Jacket): Metal cased and full metal jacket both refer to bullets with a metal coating that covers all of, or all but the base of, a bullet.
- MC (Metal Cased): This is a term used by Remington to refer to their full metal jacketed bullets.
- HP (Hollow Point): Hollow point bullets have a concave shaped tip that facilitates rapid expansion of the round upon impact.
- BT (Boat Tail): Boat tail bullets have a streamlined base to facilitate better aerodynamics.
Sometimes, these terms are mixed to make a new acronym.
- FMJBT (Full Metal Jacketed Boat Tail): Full metal jacket boat tail ammunition commonly refers to rife ammunition with the boat tail design that incorporates a copper jacket.
- JHP (Jacketed Hollow Point): Jacketed hollow point bullets are similar in design to regular hollow point bullets, but have a copper jacket that normally covers everything but the hollowed portion of the round.
- JFP (Jacketed Flat Point): Jacketed flat point rounds have a flat area of exposed lead at the tip.
- JSP (Jacketed Soft Point): Jacketed soft point bullets usually have a spire pointed tip of exposed lead. JSP can also refer to a Jacketed spitzer point; spitzer meaning a sharply pointed bullet.
- JRN (Jacketed Round Nose): Jacketed round nose bullets split the difference between JFP and JSP bullets and have a rounded tip of exposed lead.
- BTHP (Boat Tail Hollow Point): BTHP ammunition commonly refers to rife ammunition with the boat tail design that utilizes an expanding hollow point design.
- BTSP (Boat Tail Soft Point): Sometimes the letters in the acronyms are switched, so boat tail soft point may also be abbreviated as soft point boat tail or SPBT.
- EFMJ (Expanding Full Metal Jacket): Expanding full metal jacketed rounds appear as and feed like a regular full metal jacket bullet, but have a construction that allows the case to collapse and the bullet to flatten upon impact.
- WC (Wad Cutter): Wad cutter designs often appear to be nothing more than a cylinder, usually with a hollow base. This design is used in target practice to punch neat holes in the paper, rather than the ragged holes produced by more rounded designs.
- SWC (Semi Wad Cutter): Semi wad cutter bullets have a rounded nose that comes down to a cylinder that is slightly larger than the rounded section, giving the bullet a more aerodynamic shape while allowing it to punch clean holes in paper targets.
- RFP (Rounded Flat Point): Rounded flat point bullets have a flat tip that is smaller than the bullet diameter and rounded shoulders.
- AP (Armor Piercing): Armor piercing ammunition can have bullets with a variety of shapes, though in general they are spire pointed and full metal jacketed rounds that have a strong core designed to penetrate armor.
- API (Armor Piercing Incendiary): Armor piercing incendiary ammunition has the same penetrating abilities of armor piercing bullets, but with the added function of bursting into an intense flame upon impact.
- Frangible: Frangible ammunition is available under a number of trademarks; notably MagSafe, Glaser, and SinterFire. All of these rounds are characterized by a design that facilitates the rapid breakup of the bullet upon impact, thus reducing the chances of over-penetration or a ricochet.
- Shotshell: Shotshell ammunition is primarilly designed for pest control and utilizes a plastic capsule filled with small pellets that spread when fired.
This list is by no means exhaustive. There are other variations in bullet designs, many of which are proprietary and made only by certain manufacturers.
If there are other bullet types you think should be listed, be sure to let us know in the comment section.
Editor’s note: This post was originally published in March of 2010. It has been completely revamped and updated for accuracy and clarity.
What does RS stand for as far as a projectile from berrys bullets?
RS – Round Shoulder ~Dave
Very Educational but now I am more confused than ever. TMI. I think there should be only three classifications, T-target, H-hunting, S-self defense. (for civilians) BUT with one exception, Maybe they should ONLY sell F-Frangible ammo in Chicago so these street fighters won’t penetrate neighbors houses and kill babies in their cribs! OR…only Two classifications; C-cheap, and E-expensive !!!
I utilized the following in a Colt Trooper II in 1981
SJFP = Semi-Jacketed Flat Point.
For example: 357 Mag 158gr SJFP
US. Border Patrol Duty Ammunition circa 1980.
CESJHP=Controlled Expansion Semi-Jacketed Hollow Point.
For example: 38 SP (+P) 158gr CESJHP
This ammunition was developed to replace the 357 Magnum duty ammunition .
Thank you for the very informative article. For me , a visual of each bullet next to the category would have been a little more helpful.
I would suggest using photos of cartridge groups that are numbered and coordinate the numbers with the list of cartridge variations.
A companion reference might be an explanation about naming cartridge and bullet sizes. What does 9mm; .45-70; .38 vs. .38spl; .556 vs .223; .410 vs. 12ga . . . For the new or casual gun fan this is very confusing and potentially dangerous.
JHP has a coating of copper or other harder-than-lead compound over the sides of the bullet (but usually not inside the hollow cavity). While this does help to reduce fouling, it has two other advantages: (1) Some semi-auto weapons may have problems with softer lead HP, but feed properly with the JHP, and (2) the JHP will give a little better penetration before expansion than the softer HP, which expands immediately. If you are hunting big game, this may make sense, to have the expansion happen deeper in the body cavity, for largest shock value. In self-defense, in my opinion, neither is a game-changer over the other. If your gun will shoot it reliably, and if you hit your target, they should do the job equally well, I think.
With all the shortages of ammo, why is it the only type I can find anywhere is FMJ? I would prefer they be making more SP or HP.
Where can I get some API type bullets for my 9mm Luger? I need some right away.
I wouldn’t mind seeing terms likr Plus +P and Hydroshock added to you list as well as a section explaining what ar grain values mean as they pertain to bulits.
Maybe you could explain to those new to guns on what ammo will fit what guns? I have a ruger lcp 380and a heritage six rough rider 22. No ida what kinds of ammo will fit these and what wont.
TSJ – Total Synthetic Jacket
Made by Federal and marketed as Syntech, They come in Red for range rounds, Blue for fragmenting defense rounds, and Purple, as a sort of combination of both. Red come in several grain weights and profiles.
Also worth mentioning reloading component bullets made by BlueBullets They’re blue, and they’re used extensively by competition shooters who load to power factor.
What does BTP mean, when referring to a bullet?
Thanks a load, my man! That makes good sense, now that you have explained.
Have a good one.
Anytime! Thanks for reading.
I have come up against one that I am unsure of what it means. RSFP …Round S– Flat Point?? Round sides? Surplus? Squished? Hell, I don’t know! Can anyone out there help this Old Man clear up this confusion?
If it helps any , the ammo is on website -> AmmoMart and is list thusly: .32 H&R Magnum Overstock Ammo 90gr RSFP – 50 Rounds
The closest I can compare it to is,
RFP: Rounded Flat Point (see list above in article)
Thanks & Regards,
It should stand for “Round Shoulder Flat Point.”
What does “BK” mean in the 5.56 ammo that I have? The full designation is
1000 round bulk case
What does SJHP mean when describing a bullet style?
The semi-jacketed hollow point (SJHP) is a bullet designed to give you all the stopping power and expansion of a normal hollow point but with a bit more penetration.The partial jacket acts as a platform for creating a predictable and uniform mushrooming effect upon impact with a target. ~Dave Dolbee
I was looking for reloading data for 8208 using 69 gr bullets and the Hodgen website lists SIE HPBT – I know what the HPBT is abbreviated for (Hollow Point Boat Tail) but have not been able to find SIE anywhere (yet)
I know this is an old post, but I figured I’d help anyone else who can only find this page when searching for the SIE abbreviation (thanks to Hodgdon’s online reloading data). SIE is Hodgdon’s abbreviation for Sierra Bullets. This was gathered from the context found in this M14 forum post:
Maybe Hodgdon can take it a little easier on the abbreviations? Or provide a cipher?
Hi. What’s the similarities/differences between a JHP and HP? Which is better for self defense? I am under the impression that only difference with a JHP and HP, is the JHP leaves less lead foul up – that’s the only difference. Is that correct? Also, does one penetrate more than the other? Thank you very much.