Ammunition Basics: How to Identify Ammunition
Over the last decade, many new shooters have entered the firearms market. Some grew up around firearms, some did not. An important part of knowing how to get the most of your firearm is know what ammunition to use in it. In today's market, there are a lot of options when it comes to ammunition. Many times, terms like full metal jacket or hollow point get thrown around and it's assumed the intended audience understands what is being talked about. For the sake of those who may not understand, necessarily, let's take a step back.
Here, I have included pictures and descriptions of some popular styles of bullets. I have also included some key points in their design.
Conversion of Metric Bullet Diameters to English Standard
Diameter (in mm)
Diameter (in inches)
.308-.312 (depending on caliber)
What's in a Caliber Name
There is an impressive list of calibers out there that shooters can choose from, many of which few have heard of. Calibers have come and gone, some live long lives and some fade out before they ever become well known. To better understand what's in the name of a cartridge, it's important to understand that there are two distinct types of calibers, Metric and English Standard.
Metric- calibers that are based on the metric system of measurement, usually in millimeters.
Examples: 7.62x54R, 9.3x62 Mauser, 6.5x50 Japanese
Metric calibers are pretty simple to understand. The first number is the diameter of the bullet in millimeters. in the 6.5x50 Japanese, 6.5 refers to a bullet diameter of 6.5mm. The second number refers to the length of the casing in millimeters, so continuing with the Japanese example, the "50" is referring to a cartridge that is 50mm long.
English Standard-calibers that are based on the English Standard system of measurement, usually in a decimal of an inch.
Examples: .223 Remington, .308 Winchester, .50 Beowulf, 9mm Luger
English Standard calibers differ from metric calibers, in that they don't usually give the length of the casing in the cartridge designation. Some English standard calibers also use millimeters to refer to bullet diameter, like in the case of the 9mm Luger. This is one name used to refer to the very common 9mm cartridge found in many semi-automatic handguns. In many cases, there is a decimal in the cartridge name which refers to the diameter of the bullets in inches. In the case of the .223 Remington, the ".223" refers to a bullet diameter of .224" inches. This illustrates how confusing it can be for beginners to reloading, since the diameter and the caliber name don't match.
Metric bullet diameters can be converted to English standard. For those of you interested in reloading, many times bullets that are primarily used in metric calibers are listed in their metric and English standard designations.
Some calibers, like those popular in the 1800's and early 1900s were originally conceived with black powder as the propellant. Many of these calibers follow the rule of thumb that the bullet diameter be listed as the first number (in inches, like English standard), and the charge in black powder be listed second. Examples of these calibers include:
- .25-20 WCF
- .32-20 WCF
- .32-40 WCF
- .38-40 WCF
- .45-70 Government
Full Metal Jacket
For anyone hitting the range, the bullet of choice is more times than not going to be the full metal jacket. These bullets tend to be the least expensive, and many times are marketed as "target rounds" The name comes from the fact that the entire bullet (except the base) is jacketed with copper. Some benefits of the full metal jacket include:
- Better penetration
- Less expensive
- Easy to find
It's important to note that not every caliber is available with full metal jacket bullets. For calibers that are used primarily for hunting, full metal jacketed bullets may not be available. However for popular target shooting calibers, full metal jacket are widely available.
Bullets made as a soft point combine two things that many shooters are looking for, which are lower cost and ability to use on game. Soft point bullets are characterized by the exposed lead tip on the bullet. This exposed lead allows the bullet to expand on impact, making it legal for hunting applications. Many states have laws making full metal jacketed ammunition illegal to hunt with, because they have a tendency to travel farther. Some benefits of soft point ammunition are:
- Versatility-hunting or target practice
- Less expensive than some hunting bullets
- Safer to use for outdoor range practice
- Widely available
Advances in ballistics have created new designs that made the soft point a bit outdated, for those looking for extreme accuracy. However, the soft point bullets made by many manufactures are capable of shooting great groups, and at a much smaller price than those new designs, like the ballistic tip.
The hollow point bullet has been popular for hunting and self-defense purposes. These bullets are characterized by the hollow cavity at the point of the bullet. When fired, these bullets expand as the hollow point is forced into the target. This creates rapid expansion, sometimes over 1.5 times the original diameter of the bullet. Some advantages of hollow point bullets are:
- Excellent expansion on impact
- Deep wound channels in game, for humane shots
- Increased ballistic coefficient, for better trajectory
Many companies have done their own take on the hollow point bullet. While there are different names attached to many manufactures' hollow point bullets, the general concept is the same.
What type of bullet do you shoot most?
Round nose ammunition comes in a variety of different configurations. Round nose bullets can be round nose full metal jacket or round nose soft points. In this case, the description "round nose" only refers to the general shape of the bullet. Some benefits of round nose ammunition are:
- Better functionality in semi-automatic firearms
- Reduced deflection-great for brush hunting
- Can be used in rifles with tubular magazines
The term "round nose" is often used in conjunction with other terms to describe a bullet type, but understanding it's characteristics is very important. Many shooters find that when using common semi-automatic handguns, round nose ammunition functions far better than other types. In some cases other bullet designs, like the flat point, do not function at all. This makes understanding your ammunition that much more important. For those of you that intend to hunt using round nose ammunition, it's important to note that they encounter greater resistance from air. Thus, giving them a steeper trajectory and making it more difficult to use them for long-range shots.
While many auto-loading firearms do not handle flat point ammunition well, if at all, they still remain a relevant design. Like round nose bullets, the term "flat nose" is often used in conjunction with other forms, like flat nose soft point or flat nose full metal jacket. Some benefits to this design are:
- Better energy transfer than round nose, due to flat surface
The flat nose bullet does not appeal to many shooters, as it is not an aerodynamic design. This makes it an unfavorable design for shooters who plan to stretch the limits of a given cartridge. It does still remain in production, as many cowboy-action and silhouette shooters use flat point bullets.
The advent of the ballistic or polymer tipped bullet has created a buzz among competitive shooters as well as varmint hunters. These bullets are characterized by the polymer tip (usually vibrantly colored) at the tip of the bullet. The polymer tip of the bullet increases the ballistic coefficient, allowing for better trajectories and better control of long-range shots. Also, the polymer tip initiates a violent expansion of the bullet upon impact with the target. This is ideal for varmint hunters who want a bullet that does not leave an exit wound, meaning less damage to pelts. Some advantages of this bullet are:
- Higher ballistic coefficient-flatter trajectories
- Better expansion
- Better long-range accuracy
The ballistic tip bullet has become popular in a variety of caliber from very small varmint calibers, to the massive 50 BMG, for competition shooting at extreme ranges. Ballistic tip ammunition can be on the expensive side. However, the level of performance derived from it are hard to duplicate with other bullet types.
Common Acronyms Found in Ammunition Terminology
Full Metal Jacket
Flat Nose/Flat Point
FN or FP
Total Metal Jacket (plated, not jacketed)