The standard 300 Blackout bullet weight ranges from 110 grains for supersonic loads up to 220 grains for heavy subsonic applications.
Translated into metric, a typical .300 BLK projectile weighs between 7.1 and 14.3 grams depending on its intended purpose and velocity profile.
Commonly available supersonic bullet weights include 110-grain and 125-grain variants, while subsonic loads frequently utilize 200-grain or 220-grain projectiles.
Bullet weight varies significantly based on the projectile type, barrel length considerations, and whether the ammunition is engineered to break the sound barrier.
Consequently, a light 110-grain factory load can reach 2,350 fps, whereas a heavy 220-grain bullet travels at a whisper-quiet 1,000 fps.
300 Blackout Bullet Weight
| Bullet Weight | Weight In Grams | Example Load | Bullet Type | Muzzle Velocity | Muzzle Energy |
| 110 grains | 7.1 g | Barnes VOR-TX | TAC-TX (Copper Solid) | 2,350 fps | 1,349 ft-lbs |
| 125 grains | 8.1 g | Sig Sauer Elite Ball | FMJ | 2,200 fps | 1,343 ft-lbs |
| 150 grains | 9.7 g | Federal American Eagle | FMJ | 1,900 fps | 1,202 ft-lbs |
| 190 grains | 12.3 g | Hornady Subsonic | Sub-X | 1,050 fps | 465 ft-lbs |
| 220 grains | 14.3 g | Federal American Eagle | OTM | 1,000 fps | 488 ft-lbs |
Explaining the Table
The table above illustrates the unique dual-nature of common 300 Blackout bullet weights found in commercial factory ammunition.
- Common 300 Blackout bullet weights: The cartridge is effectively split into two distinct categories: light supersonic weights (110 to 150 grains) and heavy subsonic weights (190 to 220 grains).
- Light vs heavy bullets: Light bullets are designed for velocity, expansion, and terminal performance on game or defensive targets. Heavy bullets are designed to remain stable while traveling below the speed of sound, making them ideal for use with a suppressor.
- Why bullet weight varies between loads: The .300 AAC Blackout was intentionally designed to fire a wide variety of .30 caliber projectiles out of a standard AR-15 platform. The weight varies based on whether the shooter prioritizes supersonic energy or suppressed stealth.
- How bullet weight affects velocity: There is a massive velocity gap in this caliber. Lighter projectiles allow for more powder capacity and less resistance, pushing them past 2,300 fps. Heavy 220-grain projectiles leave less room for powder and are intentionally loaded lighter to stay below the ~1,125 fps sound barrier.
- How bullet weight affects muzzle energy: Because velocity plays a more significant role in calculating kinetic energy than mass, the light/fast supersonic bullets generate nearly three times the muzzle energy of the heavy/slow subsonic bullets.
- Why bullet weight alone does not determine ballistic performance: Projectile design dictates how the bullet behaves upon impact. A 190-grain Hornady Sub-X is engineered to expand at slow speeds, whereas a standard 220-grain OTM bullet will likely not expand at all, despite being heavier.
300 Blackout Bullet Weight Chart
| Bullet Weight | Grains | Grams | Common Use |
| Light (Supersonic) | 110 – 125 | 7.1 – 8.1 | Varmint hunting, self-defense, barrier penetration |
| Standard (Supersonic) | 147 – 150 | 9.5 – 9.7 | Range training, general plinking, target shooting |
| Heavy (Subsonic) | 190 – 220 | 12.3 – 14.3 | Suppressed tactical use, quiet target shooting, CQB |
Common 300 Blackout Bullet Weights
110 and 125 Grain Bullet Weight
Sitting at 7.1 and 8.1 grams respectively, the 110-grain and 125-grain projectiles represent the premium supersonic tier of the 300 Blackout bullet size. These bullets are exceptionally popular for hunting and self-defense because they achieve high velocities (2,200 to 2,350 fps) out of short barrels. Example loads like the Barnes 110-grain TAC-TX deliver rapid expansion and around 1,349 ft-lbs of muzzle energy.
150 Grain Bullet Weight
Weighing 9.7 grams, the 150-grain bullet is commonly used for affordable supersonic range training. While it does not achieve the blistering speed of a 110-grain load, a 150-grain FMJ (like Federal American Eagle) still travels at a respectable 1,900 fps. It provides a familiar recoil impulse for those who shoot standard .308 Winchester projectiles but loaded into the smaller Blackout casing.
190 and 200 Grain Bullet Weight
Moving into subsonic territory, the 190-grain (12.3 g) and 200-grain (13.0 g) bullets are often specialized expanding projectiles. Because subsonic bullets travel slowly (around 1,050 fps), standard hollow points will not open up upon impact. Loads like the Hornady 190-grain Sub-X utilize patented polymer inserts to force expansion at low velocities, making them highly effective for suppressed hunting or home defense.
220 Grain Bullet Weight
At 14.3 grams, the 300 Blackout 220 grain bullet is the undisputed gold standard for suppressed shooting. Nearly every major manufacturer produces a 220-grain subsonic load, usually featuring an Open Tip Match (OTM) or Full Metal Jacket (FMJ) projectile. Sitting right around 1,000 fps, these heavy bullets provide reliable cycling in suppressed AR-15s while remaining incredibly quiet.
300 Blackout Bullet Weight By Projectile Type
| Projectile Type | Typical Bullet Weight | Typical Purpose | Example Load |
| FMJ / Target | 147 – 150 grains | Supersonic range training and plinking | PMC Bronze 147gr FMJ |
| Polymer Tip / Copper | 110 – 120 grains | Supersonic hunting and self-defense | Barnes VOR-TX 110gr TAC-TX |
| Expanding Subsonic | 190 – 200 grains | Suppressed hunting and home defense | Hornady 190gr Sub-X |
| OTM / Match | 220 grains | Suppressed target shooting and tactical use | Remington UMC 220gr OTM |
Bullet Weight vs Velocity
The 300 Blackout was engineered from the ground up to fire two entirely different classes of ammunition, which makes the relationship between bullet weight and velocity incredibly stark.
When you load a light 110-grain bullet, you have a supersonic cartridge that behaves similarly to the 7.62x39mm, reaching speeds around 2,350 fps. However, when you jump up to a 220-grain bullet mass, manufacturers purposefully reduce the powder charge. The goal is to ensure the heavy bullet never crosses the speed of sound (roughly 1,125 fps depending on altitude and temperature). Therefore, a 220-grain bullet is almost universally loaded to travel at exactly 1,000 to 1,050 fps.
Bullet Weight vs Muzzle Energy
| Load | Bullet Weight | Velocity | Muzzle Energy |
| Barnes VOR-TX | 110 grains | 2,350 fps | 1,349 ft-lbs |
| Sig Sauer Elite Ball | 125 grains | 2,200 fps | 1,343 ft-lbs |
| Federal American Eagle | 150 grains | 1,900 fps | 1,202 ft-lbs |
| Hornady Sub-X Subsonic | 190 grains | 1,050 fps | 465 ft-lbs |
| Federal American Eagle | 220 grains | 1,000 fps | 488 ft-lbs |
Because the kinetic energy formula relies on velocity squared, 300 Blackout muzzle energy drops dramatically when switching from light supersonic to heavy subsonic bullets. A 110-grain bullet hits with roughly 1,349 ft-lbs of force—making it a capable deer hunting round. The heavy 220-grain bullet, despite being twice as massive, only delivers about 488 ft-lbs of energy because it is traveling less than half the speed.
300 Blackout Bullet Weight vs Other Cartridges
| Cartridge | Typical Bullet Weight | Weight In Grams |
| .300 Blackout (Supersonic) | 110 grains | 7.1 grams |
| .300 Blackout (Subsonic) | 220 grains | 14.3 grams |
| 5.56x45mm NATO | 55 grains | 3.6 grams |
| 7.62x39mm | 123 grains | 8.0 grams |
| .308 Winchester | 168 grains | 10.9 grams |
Grain To Gram Conversion
For shooters referencing metric load data or European ballistics charts, calculating the 300 Blackout bullet weight in grams is simple. One grain is equal to 0.0647989 grams.
| Bullet Weight | Grams |
| 110 grains | 7.1 grams |
| 125 grains | 8.1 grams |
| 150 grains | 9.7 grams |
| 200 grains | 13.0 grams |
| 220 grains | 14.3 grams |
300 Blackout Bullet Weight: How Much Does A Bullet Weigh?
A standard 300 Blackout bullet weighs between 110 grains and 220 grains. The most common factory bullet weights found on shelves are 110-grain projectiles for supersonic use and 220-grain projectiles for subsonic use. Translated into metric, these equivalent weights sit between 7.1 grams and 14.3 grams.
The lightest verified factory examples generally start at 90 to 110 grains, primarily utilizing monolithic copper or frangible designs. The heaviest verified standard loads max out at 220 grains (though custom 240-grain projectiles exist for specialty handloaders). There is no single universal 300 Blackout bullet weight, as the cartridge’s entire identity revolves around its ability to seamlessly switch between light/fast rounds and heavy/quiet rounds with just a magazine change.
FAQs
- How much does a 300 Blackout bullet weigh?A 300 Blackout bullet typically weighs between 110 grains for supersonic ammunition and 220 grains for subsonic ammunition.
- What is the typical 300 Blackout bullet weight?There are two typical weights: 110 grains (7.1 grams) is the standard for high-velocity defense, while 220 grains (14.3 grams) is the standard for suppressed shooting.
- How many grains is a 300 Blackout bullet?Factory 300 Blackout bullets range from 110 grains up to 220 grains.
- How many grams does a 300 Blackout bullet weigh?A .300 BLK projectile weighs between 7.1 grams (supersonic) and 14.3 grams (subsonic).
- What is the heaviest 300 Blackout bullet?In factory-loaded ammunition, 220 grains is typically the heaviest bullet available, designed to stay subsonic and cycle reliably in AR-15 platforms.
- What is the lightest 300 Blackout bullet?The lightest common standard loads are 110 grains, though some specialized frangible or extreme-velocity copper loads can drop down to 90 grains.
- Is a 300 Blackout bullet 220 grains?Yes, a 300 Blackout 220 grain bullet is the most popular and widely produced weight for subsonic, suppressed applications.
- Is a 300 Blackout bullet 150 grains?Yes, 150-grain bullets are frequently used by manufacturers like Federal and PMC as affordable, standard-velocity range and training ammunition.
- How does bullet weight affect 300 Blackout velocity?Lighter bullets (110–125 grains) are loaded to achieve supersonic speeds between 2,200 and 2,350 fps. Heavier bullets (190–220 grains) are purposefully loaded with less powder to remain subsonic, traveling around 1,000 fps.
- How does bullet weight affect 300 Blackout muzzle energy?Lighter, faster bullets generate vastly more muzzle energy (upwards of 1,350 ft-lbs) than heavy, slow bullets (which hover around 480 ft-lbs) because velocity is the dominant factor in kinetic energy.
- What is the difference between 300 Blackout bullet weight and cartridge weight?The bullet weight (e.g., 220 grains) refers only to the projectile. The complete cartridge—including the brass case, primer, and gunpowder—weighs significantly more.
- What are the common 300 Blackout bullet types?Common bullet types include Open Tip Match (OTM) for subsonic target shooting, Polymer Tipped (like the V-MAX or Sub-X) for hunting, and Full Metal Jacket (FMJ) for range training.