Ballistic Coefficient Chart By Caliber

A ballistic coefficient measures how efficiently a bullet overcomes air resistance and maintains its velocity during flight. Using a ballistic coefficient chart helps shooters compare different projectiles to understand which bullets will drop less and resist wind deflection more effectively over long distances.

Ballistic Coefficient Chart

CaliberBullet WeightBullet TypeManufacturer and Bullet ModelG1 Ballistic CoefficientG7 Ballistic CoefficientDrag Model or Source Notes
.22 LR40 grSolid Lead Round NoseCCI Standard Velocity.120Not verifiedG1 published by manufacturer
.223 Remington55 grFull Metal Jacket Boat TailHornady FMJ-BT.243Not verifiedG1 published by manufacturer
6.5 Creedmoor143 grPolymer Tip Boat TailHornady ELD-X.625.315G1 and G7 published by manufacturer
7mm Rem Mag180 grVery Low Drag Boat TailBerger VLD Hunting.673.344G1 and G7 published by manufacturer
.308 Winchester175 grHollow Point Boat TailSierra MatchKing.505.243G1 velocity dependent, G7 published
9mm Luger115 grJacketed Hollow PointHornady XTP.129Not verifiedG1 published by manufacturer
.45 ACP230 grFull Metal JacketWinchester White Box.194Not verifiedG1 published by manufacturer
Ballistic Coefficient Chart By Caliber

Chart Analysis and Statistics

  • The verified G1 BC values in this table range from .120 for the .22 LR to .673 for the 7mm Berger VLD Hunting bullet.
  • Differences between bullets of the same caliber are substantial, as seen when comparing short handgun projectiles to long, aerodynamic rifle projectiles.
  • Heavier, longer bullet designs like the 180 grain 7mm VLD demonstrate significantly higher BC values than lighter, shorter designs like the 55 grain .223 bullet.
  • The G1 values are consistently roughly double the G7 values for the same modern boat tail bullets.
  • This bullet ballistic coefficient chart must be used to compare specific bullets rather than calibers alone because bullet shape and weight dictate the coefficient, not the diameter of the barrel.
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Ballistic Coefficient Chart by Caliber

CaliberBullet WeightBullet DesignManufacturer and ModelG1 BCG7 BC
.22 LR40 grLead Round NoseCCI Mini-Mag.125Not verified
.223 Rem / 5.56 NATO77 grHollow Point Boat TailSierra MatchKing.372.190
.243 Winchester95 grPolymer Tip Boat TailHornady V-MAX.365Not verified
6.5 Creedmoor140 grPolymer Tip Boat TailHornady ELD Match.646.326
.270 Winchester130 grSpire Point Flat BaseNosler Partition.416Not verified
7mm Rem Mag162 grPolymer Tip Boat TailHornady ELD-X.631.318
.308 Winchester168 grHollow Point Boat TailSierra MatchKing.462.218
.30-06 Springfield180 grSoft Point Flat BaseRemington Core-Lokt.383Not verified
.300 Win Mag210 grVery Low Drag Boat TailBerger VLD Target.720.369
9mm Luger147 grJacketed Hollow PointFederal HST.205Not verified
.45 ACP230 grJacketed Hollow PointSpeer Gold Dot.143Not verified

Caliber and Design Comparisons

  • Modern long range calibers like the 6.5 Creedmoor and .300 Winchester Magnum display the highest overall BC values when paired with heavy match bullets.
  • Handgun calibers consistently show G1 BC values well below .250 due to their short, blunt designs.
  • Within the 30 caliber family, the 168 grain boat tail shows a higher BC than the heavier 180 grain flat base bullet, proving shape is just as important as weight.
  • Higher BC values reduce wind drift, but they do not automatically mean a bullet is more accurate or powerful at close ranges.

Bullet Ballistic Coefficient Chart by Bullet Type

Bullet TypeCaliberBullet WeightManufacturer and ModelG1 BCG7 BCNotes
Round Nose.30-30 Win170 grHornady InterLock RN.189Not verifiedBlunt nose creates high drag
Flat Base.270 Win130 grSierra Pro-Hunter.370Not verifiedGood hunting bullet with moderate drag
Boat Tail.308 Win165 grNosler Ballistic Tip.475Not verifiedTapered base reduces base drag
Hollow Point9mm Luger124 grSpeer Gold Dot.135Not verifiedWide cavity reduces aerodynamics
Polymer Tip6.5 CM143 grHornady ELD-X.625.315Tip resists deformation to maintain BC
Match.300 Win Mag230 grBerger Hybrid Target.718.368Optimized for maximum aerodynamic efficiency

Design Impact on Aerodynamics

  • Round nose and wide hollow point bullets demonstrate the lowest ballistic coefficients across all tested types.
  • Polymer tipped and dedicated match bullets show the highest efficiency numbers.
  • The transition from a flat base to a boat tail significantly improves the BC of rifle bullets by smoothing the airflow at the base of the projectile.
  • Bullet design plays a primary role in published BC values, explaining why not every bullet in a specific category performs the same way in flight.
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What Is the Ballistic Coefficient?

The ballistic coefficient is a numerical value that describes how efficiently a bullet moves through the air relative to a standard mathematical drag model. A higher number means the bullet cuts through the air better, loses velocity slower, and is less affected by wind drift.

  • BC measures the ratio of a bullet’s sectional density to its coefficient of form.
  • Long, sleek bullets with heavier mass relative to their diameter generally have higher BC values.
  • Values vary between bullets of the same caliber because a flat nose bullet experiences much more air resistance than a sharply pointed bullet of the exact same weight.
  • The G1 drag model represents a flat based projectile with a moderately pointed nose, while the G7 model represents a modern boat tail projectile with a long, sharp nose.
  • Some bullets have different published BC values at different velocity ranges because their aerodynamic drag changes as they transition from supersonic to subsonic speeds.
  • BC alone cannot predict a bullet’s complete trajectory because muzzle velocity, environmental conditions, and atmospheric pressure all play critical roles in where the bullet will impact.

How to Calculate Ballistic Coefficient

Figuring out how to calculate ballistic coefficient requires more than simply knowing the bullet weight and caliber. You need specific data about how the bullet behaves in flight over a known distance.

  1. Manufacturer-published BC: The most reliable method is to use the exact value provided by the bullet maker for that specific product, making sure to note whether it is a G1 or G7 value.
  2. Measured or modeled BC: You can estimate a bullet’s BC by measuring its exact velocity at the muzzle and then measuring its velocity again at a known distance downrange, such as 100 or 200 yards. By comparing how much speed the bullet lost over that distance against how much speed a standard reference projectile would lose, you can determine its relative efficiency.
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A basic muzzle velocity measurement alone is insufficient. Calculating a reliable BC requires multiple data points and a clear understanding of the reference drag model being used.

To achieve a meaningful BC estimate, you need:

  • Accurate muzzle velocity.
  • Accurate remaining velocity at a specific downrange distance.
  • The exact distance between the two velocity measurements.
  • Atmospheric data including temperature, altitude, and barometric pressure.
  • The specific reference drag model you are comparing the bullet against.

G1 vs. G7 Ballistic Coefficient

FeatureG1 Ballistic CoefficientG7 Ballistic Coefficient
Reference modelBased on a flat-based bullet with a short, blunt noseBased on a boat-tail bullet with a long, sharp nose
Common applicationsPistol bullets, traditional hunting bullets, slug roundsLong range rifle bullets, modern match projectiles
Bullet designsBest suited for flat base and round nose designsBest suited for low drag, boat tail designs
Comparing published valuesValues are numerically higher and often velocity-dependentValues are numerically lower and remain more stable across velocities

Practical Differences in Drag Models

  • G1 numbers will always look higher than G7 numbers for the exact same bullet.
  • Using a G1 model for a modern boat tail bullet requires multiple different BC values at different speeds to remain accurate.
  • The G7 model provides a more consistent, single value prediction for modern long range rifle bullets across their entire flight path.
  • These values cannot be directly converted into one another without advanced ballistic software.

Factors That Affect Ballistic Coefficient

Bullet shape and aerodynamic design dictate how smoothly air flows over the projectile. A sharp, streamlined nose creates a smaller shockwave than a blunt, rounded nose, significantly reducing frontal air resistance.

Bullet mass and diameter work together to determine sectional density. A heavier bullet of the same diameter carries more momentum to push through the air, resulting in a higher ballistic coefficient than a lighter bullet of the identical shape.

Boat-tail and nose design are critical for rearward aerodynamics. A tapered boat-tail reduces the low pressure vacuum that forms behind the bullet in flight, which drastically cuts down on total drag and raises the BC value.

Velocity-dependent changes in drag occur because air behaves differently at supersonic speeds compared to subsonic speeds. As a bullet slows down, its drag profile changes, which means its actual ballistic coefficient fluctuates during flight.

The selected G1 or G7 model directly determines the published number. The BC is not an absolute physical property of the bullet; it is a comparative rating against a specific mathematical standard.

Manufacturer measurement and reporting methods also cause variations. Different companies test their bullets at different atmospheric conditions, barrel twist rates, and velocity bands, which leads to slight differences in published numbers for very similar projectiles.

Frequently Asked Questions

What is the ballistic coefficient?

The ballistic coefficient is a number that represents how efficiently a bullet travels through the air and resists aerodynamic drag compared to a standard reference projectile.

What is a ballistic coefficient chart?

A ballistic coefficient chart is a reference table that lists the published aerodynamic efficiency numbers for various specific bullets to help shooters compare their flight characteristics.

How do you read a ballistic coefficient chart by caliber?

You read it by locating your specific caliber, finding the exact bullet weight and design you are using, and looking at the corresponding G1 or G7 value to understand its relative aerodynamic efficiency.

How do you calculate ballistic coefficient?

You calculate it by measuring the bullet’s exact velocity at the muzzle and at a known distance downrange, then comparing that velocity loss against a standard reference drag model.

What is the difference between G1 and G7 ballistic coefficient?

The G1 coefficient is based on a flat based reference bullet with a blunt nose, while the G7 coefficient is based on a modern boat tail reference bullet with a long, sharp nose.

Does a higher ballistic coefficient mean better accuracy?

No, a higher number only means the bullet is better at resisting wind and maintaining speed; actual accuracy depends on the rifle barrel, ammunition consistency, and the shooter.

Do heavier bullets always have a higher ballistic coefficient?

Not always. While heavier bullets generally carry more momentum, a lighter bullet with a highly aerodynamic boat tail and polymer tip can have a better coefficient than a heavier flat nose bullet.

Why do bullets of the same caliber have different BC values?

They have different values because bullet shape, length, and base design impact air resistance just as much as the caliber diameter itself.

Where can you find a bullet’s ballistic coefficient?

You can find it printed on the ammunition box, published on the bullet manufacturer’s website, or listed in specialized reloading manuals and ballistic charts.

How does ballistic coefficient affect bullet trajectory?

A bullet with a higher coefficient will lose velocity more slowly, resulting in less vertical drop over distance and less horizontal deflection from crosswinds.

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