The G1 and G7 drag models use different number systems to represent the drag characteristics of bullets. These number systems are known as drag coefficients.
In the G1 drag model, the drag coefficient is represented by a single dimensionless number assigned to a bullet. The G1 drag model assumes a specific reference projectile shape known as the G1 standard projectile. The drag coefficient for a bullet in the G1 model is denoted as 0.590
On the other hand, the G7 drag model also uses a dimensionless drag coefficient, but it takes into account the specific shape and characteristics of the bullet being analyzed. The G7 drag model assumes a different reference projectile shape known as the G7 standard projectile. The drag coefficient for a bullet in the G7 model is denoted as .302
The key difference is that the G1 model uses a single, generalized reference shape for all bullets, while the G7 model considers the individual characteristics of each bullet design. This allows the G7 model to provide a more accurate representation of the bullet's drag characteristics and its ability to overcome air resistance.
When comparing the ballistic coefficients derived from the G1 and G7 drag models, you will be comparing the drag coefficients assigned to the bullets using the respective reference shapes (G1 or G7) within each model.
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The G1 drag model uses a number scale to represent the drag coefficients of bullets, ranging from best (lowest drag) to worst (highest drag). The lower the drag coefficient, the better the bullet's ability to overcome air resistance and maintain velocity.
In the G1 drag model, the scale starts with a baseline value of 0.5, which is assigned to the G1 standard projectile. This reference projectile represents a relatively blunt shape with a flat base. Bullets that have a lower drag coefficient than the G1 standard projectile will have values less than 0.5, indicating better aerodynamic performance.
Here is a rough scale of G1 drag coefficients from best to worst, along with examples of projectiles that fall within each category:
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Very Low Drag: Drag coefficients significantly lower than 0.5.
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Examples: Modern long-range, high-ballistic-coefficient bullets designed for extreme precision shooting, such as the Hornady ELD-Match or Sierra MatchKing bullets.
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Low Drag: Drag coefficients ranging from approximately 0.4 to 0.5.
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Examples: Streamlined hunting bullets designed for long-range accuracy, such as the Berger VLD Hunting or Nosler AccuBond Long Range bullets.
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Medium Drag: Drag coefficients ranging from approximately 0.5 to 0.6.
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Examples: Traditional hunting bullets with slightly less streamlined designs, such as the Speer Hot-Cor or Remington Core-Lokt bullets.
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High Drag: Drag coefficients ranging from approximately 0.6 to 0.7.
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Examples: Older bullet designs with less streamlined shapes, such as military surplus ammunition or traditional lead-tipped hunting bullets.
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Very High Drag: Drag coefficients above 0.7.
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Examples: Bullets with highly non-streamlined shapes, such as shotgun slugs or specialized projectiles designed for specific applications where aerodynamic efficiency is not a primary concern.
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It's important to note that the exact drag coefficients can vary depending on the specific bullet design, velocity, and atmospheric conditions. The scale provided here is a general representation to illustrate the concept, but actual values may differ for different bullet models.
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The G7 drag model also uses a number scale to represent the drag coefficients of bullets, ranging from best (lowest drag) to worst (highest drag). Similarly to the G1 model, a lower drag coefficient indicates better aerodynamic performance in the G7 model.
In the G7 drag model, the scale starts with a baseline value of 1.0, which is assigned to the G7 standard projectile. This reference projectile represents a more streamlined shape compared to the G1 standard projectile, and it is designed to be a better representation of modern, high-performance bullets.
Here is a rough scale of G7 drag coefficients from best to worst, along with examples of projectiles that fall within each category:
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Very Low Drag: Drag coefficients significantly lower than 1.0.
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Examples: Advanced, long-range projectiles with exceptional aerodynamic performance, such as the Hornady ELD-X or Berger Hybrid bullets.
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Low Drag: Drag coefficients ranging from approximately 0.9 to 1.0.
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Examples: High-ballistic-coefficient bullets designed for precision shooting, such as the Sierra MatchKing or Nosler RDF bullets.
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Medium Drag: Drag coefficients ranging from approximately 1.0 to 1.1.
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Examples: Streamlined hunting bullets designed for long-range accuracy, such as the Barnes Tipped Triple-Shock or Berger VLD Hunting bullets.
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High Drag: Drag coefficients ranging from approximately 1.1 to 1.2.
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Examples: Traditional hunting bullets with less streamlined designs, such as the Remington Core-Lokt or Winchester Power-Point bullets.
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Very High Drag: Drag coefficients above 1.2.
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Examples: Bullets with less efficient shapes or specialized projectiles designed for specific applications, such as military surplus ammunition or certain shotgun slugs.
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It's important to note that, as with the G1 scale, the exact drag coefficients within the G7 model can vary depending on factors like bullet design, velocity, and atmospheric conditions. The scale provided here is a general representation to illustrate the concept, but actual values may differ for different bullet models.