The Hornady 139 grain SST (Super Shock Tip) in 7mm-08 Remington is a popular choice among hunters and target shooters alike. Its reputation for accuracy and consistent performance makes it a worthwhile subject for detailed ballistic analysis. This post will delve into the ballistics of this specific cartridge, exploring its trajectory, energy retention, and suitability for various hunting applications. We’ll also examine factors that can influence its performance.
Understanding Ballistic Coefficients and Their Impact
Before diving into specifics, it's crucial to understand the concept of ballistic coefficient (BC). The BC is a measure of a projectile's ability to overcome air resistance. A higher BC means less drag, resulting in a flatter trajectory and better long-range performance. The Hornady 139 gr SST in 7mm-08 generally boasts a respectable BC, although the exact figure can vary slightly depending on the manufacturing batch and testing conditions. This variation is a normal part of ammunition production and should be expected.
Hornady 139 gr SST Ballistics Data: What to Expect
The data presented below is based on average values and should be considered a general guideline. Actual performance can vary depending on several factors, including:
- Muzzle Velocity: This is heavily influenced by the specific firearm, barrel length, and powder load. A longer barrel typically yields higher velocity.
- Altitude: Air density decreases with altitude, affecting drag and consequently, trajectory.
- Temperature: Colder air is denser, resulting in increased drag.
- Wind Conditions: Wind significantly impacts bullet trajectory, especially at longer ranges.
Therefore, always consult your specific firearm's manual and conduct your own zeroing and testing to establish accurate data for your setup.
Typical Ballistic Data (approximate values, based on a 22" barrel):
- Muzzle Velocity: Approximately 2650 fps (feet per second)
- Muzzle Energy: Approximately 2,800 ft-lbs (foot-pounds)
- Energy at 300 yards: Substantially reduced, precise figures requiring specific ballistic calculators and conditions.
- Trajectory: Will depend on your zero distance. Expect a trajectory that is manageable for most hunting situations within its effective range.
It's important to note that energy retention is crucial. While the bullet will retain a significant amount of energy at medium ranges, this will reduce as range increases.
Hunting Applications: Where the 139 gr SST Excels
The 139 grain SST is a versatile bullet well-suited for a variety of game. Its relatively flat trajectory and good penetration make it effective on medium-sized game such as deer, antelope, and hogs. However, it might not be ideal for extremely large or thick-skinned animals where heavier bullets with higher sectional density might be preferred.
Factors Affecting Accuracy and Performance
Several factors influence the accuracy and overall ballistic performance of the Hornady 139 gr SST in 7mm-08:
- Rifle Accuracy: The inherent accuracy of your firearm plays a significant role. A well-maintained rifle with a properly bedded action is crucial.
- Ammunition Quality: Consistency in ammunition is paramount. While Hornady is known for its quality, variations can still exist between batches.
- Sight-in Process: Proper zeroing of the rifle at your chosen range is essential for accurate shot placement.
- Shooting Technique: Good shooting techniques, including proper stance, breathing, and trigger control, significantly impact accuracy.
Conclusion: A Solid Performer for Many Applications
The Hornady 139 gr SST in 7mm-08 is a consistently popular choice for a reason. Its balance of accuracy, energy retention, and versatility makes it suitable for various hunting applications. Remember to always conduct thorough research, practice safe handling procedures, and understand the limitations of your chosen ammunition and firearm to optimize performance and ensure ethical hunting practices. Utilize ballistic calculators and chronographs to fine-tune your understanding of this cartridge's performance in your specific setup.