What Is Bullet Grain? Discover How Grain Affects Performance

When you pick up a box of ammo, you may zero in on that mysterious ‘grain’ metric. But what exactly is bullet grain, and should shooters, hunters, and enthusiasts really pay much attention to it? In this guide, you’ll learn all about what bullet grain is, the types of bullet grains, and how to choose between them!

Simply put: Bullet grain refers to a bullet’s weight. This weight impacts accuracy, recoil, speed, and power. When you look at an ammo box, you’ll most commonly see two shortened abbreviations: ‘GR’ or ‘GRS’ — both represent bullet grain.

A single grain is just 1/7,000th of a pound (or about 1/437.5th of an ounce). To help you better realize just how small a bullet grain is, here are a few examples of everyday, common objects’ weight in grains:

• Penny = 38.6 grs

• Paper clip = 14.96 grs

• Postage stamp = 2.83 grs

But what parts of a round actually matter when it comes to grain count? In general, you’ll find four components that make up one bullet: the projectile, cartridge, powder, and primer. Bullet grain only refers to the weight of the projectile.

You can tell what a bullet’s grain is by reading the information written on the ammunition box by the manufacturer. While different grains have different benefits, it’s important to remember that every type of gun can only use a specific range of bullet grain.

Bullet grain should be an important consideration for shooters who prioritize better performance (or accuracy) and terminal ballistics.

• Bullet grain greatly influences your firearm’s performance: helping a bullet to maintain its path and retain effectiveness in various conditions. Grain cannot save a poorly lined up shot. However, paired with practice and skill, bullet grain can help you achieve better overall accuracy.

• Grain also impacts terminal ballistics, which includes factors like trajectory, velocity, and energy upon impact. Heavier bullets typically maintain their strength well, allowing them to sink deeper into their targets. Lighter bullets, on the other hand, travel faster and stay on course better.

• The right bullet grain can help you feel more comfortable while shooting. Improved recoil and control help make for a better overall experience.

• When using a compensated firearm, use lighter grains to get the maximum benefit (more energy to shoot the projectile).

• Minimize the point of impact (POI) shift by using the same grain weight for practice (where you’ll most likely use ball or FMJ ammo) and self defense ammo (typically hollow point ammo).

Bullet grain affects accuracy by influencing stability and matching the gun’s twist rate. Twist rate is how fast the barrel spins the bullet to keep it stable.

• Heavier bullets need a faster twist rate to stay steady and accurate.

• Lighter bullets can stay stable with a slower twist rate.

Matching the right bullet with the correct twist rate helps the bullet fly straight and true. Using the right bullet grain with the right twist rate is key for the best accuracy and performance in shooting.

Range and practice shooting offers both indoor and outdoor venues. However, outdoor uses like hunting and sport shooting include environmental factors like wind and distance. Temperature, humidity, and altitude can impact bullet performance when shooting outdoors:

• Higher temperatures and lower humidity decrease air density, allowing bullets to travel faster and with less drag.

• Similarly, shooting at higher altitudes can increase the range and flatness of a bullet's trajectory. Have a couple ammo boxes with different bullet grains on hand for different conditions.

• When using a rifle, match your grain to your firearm’s twist rate.

• More humidity increases drag. Aim your firearm a little higher when shooting in higher humidity.

• Keep a couple of different bullet grains in the calibers you use on hand, so you’re able to gauge the weather conditions and compensate accordingly.

The shape of the bullet and how fast it's going can affect how much drag it feels. In shooting, minimizing drag is important because less drag means the bullet can travel farther and stay on target more accurately.

Imagine you're throwing a ball through the air. When you throw it, the air around the ball pushes against it, making it slow down a bit. This push from the air is what we call ‘drag’.

Now, think of a bullet flying through the air after you fire your gun. Just like the ball, the air around the bullet pushes against it as it moves forward. This air resistance (or bullet drag) slows down the bullet as it travels.

Bullet grain varies by caliber. That means what’s considered light for a handgun’s 9mm wouldn’t apply to the rifle’s 5.56mm. Projectile weight (bullet grain) ranges from 15 grs for smaller calibers to 700 grs for larger ones.

Overall, caliber plays a crucial role in a projectile's weight. A bullet caliber indicates the internal diameter of a gun barrel and — in turn — the diameter of the bullets designed to fire from that firearm. Let’s explore the different ranges in popular bullet grains for the most popular calibers:

Explore light vs heavy grain by using the following links:

• When to use light grain

• When to use heavy grain

Light bullet grain is most commonly used in situations where precision and control are essential, such as:

• Range Shooting & Practice

• Sport Shooting

• Varmint Hunting

Range and practice shooting depend on a combination of your shooting skills plus the bullet’s natural accuracy and performance. Using lighter projectiles for practice makes for a more comfortable shooting experience. They also help novice shooters get to know their specific firearm’s handling and other characteristics.

For sport shooting at long distances, choose lighter bullets. Lighter bullets move faster and stay on course better. Keep in mind, though, that wind affects them more. Always pick bullet weights based on the expected wind conditions to improve accuracy.

Rifle shooters should consider which type of rifle to use. Different rifles work better with certain bullet weights because of how fast the barrel twists.

• Lighter bullets often work better with rifles that have faster barrel twists.

• Shooters can match bullet weight with the rifle's twist rate by checking the manufacturer's recommendations.

Varmint hunters can also use lighter bullets. These small, fast projectiles work well for hunting small animals and pests. They move quickly and stay accurate over short to medium distances. The lighter weight means less recoil, so hunters have better control and precision.

Heavy bullet grain is most commonly used in less controlled environments and situations where strength and power are needed, such as:

• Hunting

• Self-defense

Heavier bullets hit harder, which is great for hunting different, larger animals. Hunters who want quick and ethical kills may choose heavier bullets. However, heavier bullets move slower. Using heavier grains might mean that you need to change how you shoot. (getting closer to the target or aiming more carefully, for example).

Self-defense usually happens at close distances. At close range, heavier bullets are better because they cause more damage — effectively stopping targets faster. Choosing heavier bullets helps protect others in public situations, since heavy grain projectiles tend to not penetrate all the way through the target.

Heavy grain bullets do cost more; however, practicing with them:

• Helps you prepare

• Load the bullets correctly

• Shoot accurately when it counts

When should you choose light vs heavy bullet grain? Light grain bullets are perfect for range, sport, & practice shooting plus varmint hunting (small animals). Heavy grain bullets suit hunting large game as well as self-defense purposes.

Given how much the grain impacts the projectile’s path and accuracy, opting for the right weight can improve your shooting skills! Either way, you shouldn’t just choose the cheapest ammo box in the aisle. Take a look at this summary:

Choosing the right bullet grain depends on what firearm you have, how you plan to use it, and your personal preferences.

• Step 1: Decide on your firearm's use — Determine if you will use your firearm for target practice, hunting, sport shooting, or self-defense.

• Step 2: Consider your shooting goal — Lighter grains for long-distance accuracy. Heavier grains for better stopping power in self-defense. Consider wind and distance for hunting and sport shooting.

• Step 3: Consider environmental factors — Evaluate how temperature, humidity, and altitude affect bullet performance: Higher temperatures and lower humidity make bullets faster. Shooting at higher altitudes can extend bullet range and straighten trajectory.

• Step 4: Match bullet grain to your firearm — Follow the manufacturer’s or a professional’s recommendations. Factor in your firearm’s barrel length for optimal bullet speed and stability.

• Step 5: Test different bullet grains — Experiment with shooting various grains to find what suits you best in terms of recoil, accuracy, and handling.

• Step 6: Check cost and availability — Compare the cost and availability of different bullet grains: Common bullet grains are cheaper and easier to find. Specialized bullet grains may be more expensive and harder to find.

• Step 7: Seek advice from experienced shooters — Get recommendations from experienced shooters in your area of interest: Join hunting communities, sport shooting forums, or self-defense groups for valuable insights.

Ready to find the perfect ammunition for your shooting needs? With a wide selection of top-quality ammunition for all activities. From target practice to hunting and self-defense, Academy Sports + Outdoors has you covered! Shop online or visit your nearest store today to discover the right bullet grain for your firearm.