[ED: Here’s an old Ask Foghorn post that addresses a question we get frequently.]
Reader Randall writes:
While I’m not exactly a newbie when it comes to *using* firearms, I am a newbie gun *owner*. And now that I’m in the position of purchasing ammo, I’m finding things to be rather confusing when sorting out all there is to be had.
I think I’ve kind of figured out what I want to buy for my Springfield XD 9mm, but choosing ammo for my AR-15 is proving to be more daunting.
How ’bout an article for us newbie-types explaining the differences between, say, “full metal jacket” versus “total metal jacket” versus “jacketed hollow point” versus “jacketed hollow point subsonic” versus “frangible” versus “full metal jacket boat tail” versus “soft point” versus “boat tail hollow point” versus “lead round nose” versus “safety slug” versus…you get my drift.
That’s a pretty wide-ranging question, so I’ll answer it in three parts. Part one is all about the different types of projectiles and there are quite a few. But first, in order to explain the different designations, a little about how bullets are made.
A few weeks back, I took a trip to the Hornady manufacturing plant in Grand Island, Nebraska. It’s a good read in itself and I recommend you take a look, but this picture is the one we really want to focus on.
The vast majority of bullets are constructed of a solid lead core with a copper covering (called a “jacket”) that contains the lead. Lead is used because it’s an extremely dense, yet cheap metal, making it perfect for giving projectiles their weight while keeping the overall size small. Copper is used because it’s strong enough to keep the softer lead from de-forming, but soft enough to allow the gun’s rifling to “grip” the bullet.
The copper jacket starts out as a cup, having been cut from a long sheet. Through a process called “drawing,” the cup is lengthened and shaped to fit the profile of the projectile they’re making. These cups will eventually end up as jackets for 5.56 NATO rounds.
However, while this process is very efficient, it’s extremely difficult to actually get the metal to encase the entire lead core without any gaps. To keep production costs down, bullet manufacturers usually leave one end of the projectile open. Which end is open – and how that’s done – determines the classification of the projectile.
Here are three 150 grain .308 caliber bullets (a “grain” is a unit of bullet weight). And while they look very similar, the way in which they were manufactured is very different. The first projectile on the left is a “full metal jacket” (FMJ) round with a solid copper point. The other two are an open tip and a soft point bullet respectively, with openings in the copper at the tips of the projectiles.
Looking at the bases of the bullets we can see why they’re different. The “full metal jacket” bullet actually has an opening, but it’s at the bottom of the round. So what makes these bullets different? Let’s go over each one.
Full Metal Jacket (FMJ)
“Full Metal Jacket” or “FMJ” projectiles usually aren’t actually fully jacketed, but simply have a copper jacket covering the top of the projectile. Military FMJ ammunition is completely covered by a copper jacket (as per the Hague Conventions), which uses a more involved process than traditional civilian ammunition (but doesn’t alter the lethality of the rounds at all).
FMJ ammunition is manufactured so that the bottom of the original cup of copper becomes the tip of the bullet, producing a continuous jacket of copper over the top of the round. However, most civilian ammunition leaves the base of the lead core uncovered, as illustrated with the bullet on the left in the above images (the ones with the three bullets side by side).
FMJ ammunition is cheap to produce, and therefore is the traditional choice for use on the firing range. The uniform and aerodynamic design of the projectile also makes it the ideal choice for long range precision shooting.
However, that streamlined design means that it’s also more likely to penetrate a living target (like a human or an animal) and keep going out the other side, possibly injuring people further downrange and leaving only a small wound in the target. Therefore, for home defense and hunting it’s not advisable to use FMJ ammunition.
There are a couple variations of FMJ ammunition that can be recognized by their designations:
- Round Nose (RN) — The tip of the bullet is rounded in a spherical shape, which is not particularly aerodynamic. This is used mostly in handgun ammunition and older rifle ammunition.
- Boat Tail (BT) — The rear of the bullet is tapered to give it a more aerodynamic profile (the two bullets on the left in the images above). This is common in “match” grade rifle ammunition and long range target ammo.
FMJ ammo is the “default” ammunition style, and the only one where the jacket is drawn from the tip. Every other projectile uses a jacket that is drawn from the base, and the tip is usually designed to perform some sort of function.
Open Tip (OTM)
Again, with FMJ rifle rounds, the bottom of the cup becomes the tip of the bullet. With “open tip” bullets, the opposite is true — the bottom of the cup is the bottom of the bullet. While this covers more of the lead core than the FMJ projectile, it leaves a small opening at the tip of the bullet where the jacket was drawn together. Many people mistake this for hollow point ammunition, but the point is too small to work that way.
Open tip bullets are preferred by long distance shooters as the manufacturing process is more consistent than with FMJ projectiles. That leads to higher quality bullets and better performance at long distances. These projectiles are often referred to as “OTM” or “open tip match” to indicate that they’re held to a higher standard than regular range ammunition.
Due to the construction of the projectiles, open tip bullets perform nearly identically to FMJ projectiles when they strike the target.
Hollow Point (HP)
For self-defense or hunting, hollow point bullets are the way to go. Following the same general manufacturing process as the “open tip” bullets, these projectiles feature an exaggerated opening at the front of the bullet. The idea is that this opening will force the projectile to expand upon impact with a target, dumping all of the energy of that round and creating a bigger wound with more “stopping power.”
However, that gaping hole in the front of the bullet in self-defense rounds also creates an immense amount of drag as it travels through the air and negatively impacts its long range capabilities.
Gun control advocates have successfully branded hollow point self-defense rounds as “cop killer” bullets in some states and have implemented legislation banning their use. Some believe they are “armor piercing” but as we have tested and proven, that’s not the case.
Hollow point ammo is the favorite choice for police officers and those who carry a concealed weapon for one simple reason: when a JHP round hits something, it stops. They don’t keep going like FMJ rounds can, potentially injuring people on the other side of the target.
Soft Point (SP)
While hollow point ammunition is great for handgun rounds at close range, when you’re hunting at longer ranges with a rifle you need a round with better ballistic properties. One of the first attempts to make a projectile with the accuracy of a FMJ bullet and the “terminal ballistics” (how well it does when it hits a target) of a hollow point round was the “soft point” bullet.
The main difference between a soft point bullet and an open tip bullet is that with the soft point, some of the lead core protrudes from the front of the round. This gives the bullet a more aerodynamic shape than the open tip bullets, and also has a tendency to flatten the projectile when it hits a target. The bullets don’t open up as dramatically as a hollow point round, but it’s still an improvement. Especially where hollow point rounds are illegal.
But if you’re looking for a type of bullet that’s a really good hunting round, there’s something far better out there than a soft point bullet.
Ballistic Tip
How do you get the benefits of a hollow point with the long range accuracy of a FMJ? By adding a small piece of plastic. “Ballistic tip” bullets feature an exaggerated opening in the tip of the copper jacket to allow the bullet to expand upon impact. But that hole is covered by a cone-shaped piece of plastic that allows the bullet to perform as if it were a FMJ. It’s a pretty nifty design, and one that I use to great effect in my hunting ammunition.
Other Bullet Types
While a lead core is the standard for bullet construction, there are some other interesting designs that are purpose-built for specific roles. Here are a few:
- Frangible — These bullets are made out of compressed granules of copper, and are designed to shatter upon impact with a hard surface. They are used mainly as training ammunition in shoot houses, where over-penetration is a serious concern.
- Standard Copper — Copper-only bullets are extremely effective and they’re available in a variety of bullet types and weights. Eliminating the lead core keeps more lead out of the environment and some states have mandated their use for hunting.
- Total Metal Jacket (TMJ) — Lead core bullets that are totally encased in copper to reduce lead exposure. Some indoor ranges require this as it reduces the amount of lead particles in the air.
- Jacketed Flat Nose — A jacketed bullet usually used in lever-action rifles
- Steel Core / Armor Piercing — The lead core is replaced with a solid dart-shaped chunk of steel, designed to pierce body armor and some thinner-skinned vehicles. This can ruin steel targets, and cause ricochet hazards if used improperly.
- Tracer — Bullets are treated with a chemical (usually phosphorus) that burns as the round flies downrange. This allows shooters to see where their bullet flies, but also keeps burning after the projectile lands and can be a fire hazard.
That’s a good introduction to the different types of rifle bullets and why they’re used. If you’d like more information on this or other firearms topics, let us know.
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That was informative. It has come a very long way from melting lead and pouring it in a mold no doubt. The old timers used to make dum sums before hollow points for pistols was a thing
Proofread possum, proofread, Dum Dums
Maybe he was trying to say dim sum. He must be hungry
…and maybe he was correcting himself in a reply due to no option to edit.
i think he meant double tapas.
If you are going to repost old content can you at least do an update and include the newfangled solid copper defense rounds?
The article mentions solid copper, but just refers to it a little different, so you just have to read the article instead of skimming.
“Standard Copper — Copper-only bullets are extremely effective and they’re available in a variety of bullet types and weights. Eliminating the lead core keeps more lead out of the environment and some states have mandated their use for hunting.”
I was at the range one day, and the guy next to me had been invited to a hunt and was trying all copper ammo for the first time. .22LR I think. He said the accuracy was horrible. I doubt that there is anything inherently bad about pure copper, but be forewarned.
I did not know about “open tip.” Thanks.
I knew someone who tried to use OTM ammunition (.308 155g Palma Match) for hunting. I told him the results will vary. And they did. Some opened nicely and dropped several pigs. Others went like FMJs and punched straight through.
Having previously hunted with FMJs, I can tell you shot placement is paramount. With pigs I would aim for the shoulders or the front leg. The pigs wouldn’t run very far with a broken front leg.
And a friend of the person using OTM rounds would use varmint projectiles through his .243 on pigs. He chose them for the accuracy off the bench. The result was shallow cratering wounds with no real internal penetration. All the pigs had to be put down with a .22 to the back of the head.
My choice on the first trip were a 6.5×55 M96 using PMC 139g SP. Everything was a one-shot-stop. The next trip was using a 8×57 with 170g RNSPs. Also giving one-shot-stops.
Right bullets for the game will always beat benchrest results.
standard copper also keeps more lead out of your lungs, which is the part of the environment I care about most
exploding the soft lead of FMJ at the base powders more lead than the other styles
‘Explode’? Nothing explodes when a cartridge is fired. If an explosion occurred, there would be nothing left of the cartridge. Back to Physics 101 for you.
Exploding bullets and lead filled air is the reason I hold my breath and flinch.
Shattering is a better term for what happens to a lead projectile upon impact, but not in a way we usually think shattering refers to. As the lead projectile is deformed upon impact, miniscule amounts of the projectile begin to seperate from the core projectile. Lead, because of its chemical makeup, shatters less than some other materials, which is why the spent slug is typically found, but if it’s weighed, there’s usually a significant difference in the weight of deformed projectile v. an intact projectile.
Pretty sure, as in I hope he meant “exposing the lead” as this is the most simple explanation for the blunder. This was probably a phone auto-correct which are easy to overlook.
There is some additional information that could be useful here.
First, there are lead bullets, which can be “hard cast” or “soft.” Total lead bullets are often used in older cartridges which were designed from their inception to use cast lead bullets – eg, the .45-70, and similar 19th century cartridges. Some handgun cartridges also use solid lead bullets (eg, .45 Colt, .44-40, .38 Special), and most .22LR rounds are solid or hollow point lead, with perhaps only a minor flashing of copper or brass on top of the lead. “Hard cast” lead bullets will not deform much on impact with game or in a defensive use. Shooters often prefer hard cast because they leave less lead in the barrel to clean out later. “Soft” lead bullets will deform, often markedly so. They’ll also load up your bore if you allow them to do so.
Lead bullets might have a gas check on their base to allow for higher pressures/velocities.
Second, there are the brass/bronze solids meant for deep penetration on dangerous game, such as Cape Buff. These will be made by Woodleigh and others, perhaps rolled into ammo by such outfits as Kynoch. These are made to penetrate quite deeply through bone and tough hides without fragmentation or loss of mass.
Third, while varmint rounds are often lead-cored jacketed bullets, their cores are sometimes sintered metal powder inside a thin, ductile copper jacket as opposed to lead wire (or poured lead) inside a thicker copper jacket. Varmint bullets might resemble ballistic hunting bullets, but the semblance is purely cosmetic, as their interior construction is very different.
The idea of a varmint bullet is that as soon as this bullet hits something, the bullet literally explodes, dumping all its kinetic energy into a very small zone of penetration. These are used on small, thin-skinned varmints like ground squirrels and prairie dogs. If someone misses their target at a shallow impact angle, a heavier-jacketed ballistic/FMJ/etc bullet could ricochet quite a long ways; but the varmint bullet typically explodes instantly upon even a glancing impact with the soil, resulting in the bullet being scattered behind the point of impact by (typically) no more than about 10 to 20 yards.
Ah nice. I need to get some varmint bullets, then.
Thanks for the great info both author and knowledgeable commenters!
The esteemed Mr. ’22plinkster’ has neat video of the CCI .22lr ammunition manufacturing line.
It’s well worth a see :
https://www.youtube.com/watch?v=_rCZHG_eEak
‘When a JHP hits something, it stops’. Not all the time, amigo. Generalize much?
That’s twice in a very short thread that you’ve pounced on some minor error or *technically* incorrect definition.
Are you the Clark Kent who is the alter ego of Super Pedantic Man?
If he had put 97.365 percent of the time, dude would have called him out for citation of his data. Some people you just cant make happy.
Thank You for the correction…. JHP’s don’t just STOP…. they can easily hit secondary and even tertiary “targets”… Newbies NEED to hear the TRUTH about overpenetration. You can really ruin your day by hitting something beyond your intended target. Depending on caliber you could do serious, possibly fatal damage. ALWAYS check what’s beyond your target because you ARE liable for where your bullet goes, and what it destroys.
I need a bullet that works as well for Serial Deer as it does for Bigfoots. I could use shotgun slugs, I’m sure they’d work for both, but at the extreme range that most Bigfoots are shot, I couldn’t use a shotgun, me and slugs are done at about 896 yards. I’ve tried a scope on the shotgun, however after about a dozen shots the barrel gets hot, then the duct tape comes loose and the scope falls off
I miss Foghorn. Foghorn, Farrago, and, sometimes even Israeli supermodels.
Question for you shooters out there: Is there any benefit to shooting boat-tail bullets in a high-power rifle? My Savage 112SSVB shoots 190gr speer factory loads to one ragged hole at 100 yards, even with a cheap scope and non-accutrigger. Yet I was always taught that the anti-drag benefits of the boat-tail only start when the bullet drops below supersonic, which is well past 1000 yards. What do you think?
re: the above post: My Savage is a 300 Win Mag. Coffee obviously hasn’t hit bottom yet…
What I like about boat tail bullets is they’re easy to reload. They’ll sit nicely on top of the case while it’s raised up into the die.
Their higher ballistic coefficients theoretically offer two advantages: 1) Maintaining velocity over a longer distance, resulting in a flatter trajectory and a higher terminal velocity, and 2) decreased wind deflection.
I feel ya on the ease of reloading that comes with boat tails. It’s my go to for pistol as well, those XTP’s just slip right in the case with minimal belling required.
Boat tail bullets give an improved performance over flat-base Spitzer bullets when the bullet is going trans-sonic – say, Mach 1.0 down to Mach 0.85 or so. The “boat tail” helps “fill up” the void behind the bullet – but only if the angle of rebate is between 7 to 9 degrees (If my memory serves on this bit of trivia). Too extreme of a rebate angle on the boat tail and turbulence develops behind the bullet, just not in quite as an abrupt manner as it would for a flat-base Spitzer.
Here’s a practical application you can observe: Have you ever seen those “chutes” that are now attached to the rear of trailers on 18-wheelers on the highway? It forms a hollow box behind the trailer doors? That’s doing for the trailer what the boat tail does for the bullet – it’s trying to “fill up” the void behind the trailer’s flat rear surface, reducing drag and increasing fuel mileage.
Basic net:net is that boat tails are one feature that helps reduce he drag on a bullet. If your bullet is doing one-hole groups, I’d say keep using it – why mess with success?
Thanks for posting this again. I now gun control history very well. But I’m still learning about gun technology.
It’s great to learn that the vast majority of bullets are constructed of a solid lead core with a copper covering that contains the lead. I recently got into shooting ranges and using different guns. As a beginner, it’s always fun to learn so much about my hobby, and will keep this information in mind when I shoot. Thanks!
I’ve become a fan of the Barnes ttsx line of copper rifle bullets, provided your rifle shoots them accurately. Great results on meat in my experience. Pretty much a best of both worlds as far as good expansion and damage along with retaining nearly all its mass for good penetration. Not shedding any lead along the way also means you can “eat right up to the hole”.
Not being as dense as lead you typically take a step down in bullet weight than you’re likely used to using but it still works out in your favor. As lead sheds some of its material along the way, after a bit of penetration the copper one that started out a little lighter is then heavier as it doesn’t shed material.
Any recovered coppers I’ve seen usually weigh within a grain or two of their initial weight, mostly accounted for by the plastic tip.
Also seen them do very well on things like light barriers, like automobile metal and windshield glass. The front petals might fold all the way back or even shear off depending but the solid base just keeps punching through.
Something like a 165 grain in 30-06 or a 140 grain in .270 is pretty much a do everything bullet. Anything from coyote to elk or moose, one load, one trajectory holdover/under to remember does it all.
Ya I’m one of those that just uses one rather far zero, known trajectory, and just uses the view in the scope to hold over/under/windage, etc. instead of turning dials and counting clicks. Just easier for me and works good out to as far as I can make an ethical hunting kill shot every time anymore.
It’s not unlike the old M16 “battle zero”. Hold on at close range, a bit under at intermediate range, on again when you get out there, and over when you get way out there. Simple.
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