Understanding the .308 Winchester Cartridge
Overview
The .308 Winchester, often mistakenly referred to as the 7.62x51mm NATO, is a short-action rifle cartridge known for its exceptional ballistic characteristics. The .308 Winchester shares dimensional similarities with the 7.62x51mm NATO, although there are slight differences in chamber specifications. This commonality often leads to confusion, but it’s vital to understand these nuances for safe reloading practices. The .308 Winchester typically handles bullet weights ranging from 110 to 200 grains, providing flexibility across various shooting disciplines.
Performance Characteristics
When reloading the .308, the primary objectives are usually accuracy, velocity, and sufficient energy to achieve the desired effect at the target. Accuracy is paramount, whether hunting or competing; a tight group is the ultimate goal. Velocity impacts trajectory and downrange performance, affecting both bullet drop and time of flight. Energy, measured in foot-pounds, determines the effectiveness of the round upon impact, especially crucial for hunting applications. Choosing the right powder is the cornerstone of achieving these goals. The correct powder acts as the fuel that propels the bullet, optimizing velocity while ensuring safe pressure levels and consistent performance. Selecting the right powder is paramount in the journey to crafting the best powder for reloading 308.
Factors to Consider in Powder Selection
Bullet Weight and Powder Selection
The weight of the bullet is a significant determinant in powder selection. Heavier bullets typically require slower-burning powders to generate sufficient pressure and achieve optimal velocity. Conversely, lighter bullets tend to perform well with faster-burning powders. It’s important to match the burn rate of the powder to the bullet weight for the best results, ensuring complete combustion and preventing excessive pressure.
Intended Purpose and Powder Choice
The intended purpose of the ammunition dictates which powder best suits the application. For hunting, where expanding bullets and reliable terminal performance are essential, powders that provide adequate velocity and consistent expansion are crucial. For target shooting, accuracy and consistency are the primary goals. Target shooters often prioritize powders that deliver tight groups with low standard deviations in velocity. The best powder for reloading 308 for hunting and the best powder for reloading 308 for target shooting may not always be the same.
Barrel Length and Powder Considerations
The length of the rifle barrel can significantly impact the powder selection process. Shorter barrels may benefit from faster-burning powders, which can burn more completely within the shorter barrel length. Longer barrels often allow for the use of slower-burning powders, which can achieve higher velocities by providing a more extended period of pressure buildup.
Temperature Stability and Consistency
Temperature stability is a crucial factor, especially when shooting in varying environmental conditions. Temperature-sensitive powders can exhibit significant changes in velocity and pressure with temperature fluctuations. Temperature-stable powders provide more consistent performance across a wider range of temperatures, enhancing accuracy and reliability.
Availability and Cost
Availability and price are practical considerations. It is essential to select powders that are readily available to ensure a continuous supply. Price can also be a determining factor, especially for shooters who engage in frequent reloading. Finding a balance between performance and cost is often a key goal.
Safety as a Priority
Safety, above all else, must be your top priority. Always consult a reputable reloading manual and adhere strictly to the manufacturer’s load data. Start with the minimum recommended powder charge and work your way up carefully, monitoring for any signs of excessive pressure. Reloading is an enjoyable hobby but requires a commitment to safety.
Top Powder Choices for the .308 Winchester (Detailed Reviews)
Review: IMR 4064
IMR 4064 is a classic, stick powder that has been a favorite among .308 reloaders for decades. It’s a medium-burn-rate powder that excels with a wide range of bullet weights. This powder has a slightly longer stick configuration, which often contributes to excellent metering consistency. IMR 4064 is generally known for its good accuracy, especially with bullets in the 150-180 grain range.
This powder tends to deliver good velocity, allowing for flat trajectories and sufficient energy at extended ranges. While it is not entirely temperature insensitive, IMR 4064 demonstrates reasonable stability across moderate temperature variations. Load data is readily available, making it a straightforward choice for both experienced and novice reloaders. IMR 4064 is an excellent choice for both hunting and target shooting. You can find reliable load data for IMR 4064 in various reloading manuals. IMR 4064 proves itself to be a good choice in finding the best powder for reloading 308.
Review: Varget
Varget, manufactured by Hodgdon, has quickly become a standard in the reloading community. This ball powder is known for its excellent metering characteristics and impressive accuracy. Varget consistently delivers tight groups and low standard deviations in velocity, making it a top choice for target shooting and precision rifle applications.
Varget’s temperature stability is a major advantage, ensuring consistent performance across a wide range of temperatures. It is an exceptionally versatile powder, performing well with bullet weights from 150 to 180 grains. Its consistency is a key strength. Reloading data is widely available, and it meters well, making it easy to work with. Varget is a solid contender in the search for the best powder for reloading 308.
Review: Reloder 15
Reloder 15 is a slightly slower-burning powder that’s a great option for a wide variety of .308 Winchester loads, particularly when heavier bullets are being used. It provides excellent velocities and good accuracy, making it a suitable choice for hunting applications. Reloder 15 delivers high performance with excellent ballistic consistency.
Reloder 15’s versatility allows it to be effectively employed with bullets in the 165-180 grain range. Its performance is generally consistent across typical temperatures. This powder offers excellent results when properly applied. The best powder for reloading 308 will depend on the bullet weight and application and Reloder 15 is frequently the perfect fit.
Review: Hodgdon’s CFE 223
Hodgdon’s CFE 223 is a relatively fast-burning, spherical powder, often a good option for those reloading with the .308. This powder offers low copper fouling due to its CFE (Copper Fouling Eraser) technology, which helps reduce copper buildup in the barrel. CFE 223 gives the reloader a cleaner overall shooting experience.
CFE 223 excels when loaded with lighter bullet weights, typically from 110-168 grains. This powder is favored for hunting, as it offers good velocity and performance. This powder offers the benefits of low copper fouling and is readily available in many locations. CFE 223 is another excellent selection for reloading the .308 and searching for the best powder for reloading 308.
Review: Accurate 2520
Accurate 2520 is another popular powder that provides excellent versatility in the .308 Winchester. It offers excellent performance with a variety of bullet weights. Accurate 2520 has a burn rate that makes it suitable for use with bullets from 150 to 180 grains. This powder provides good velocity and accuracy.
The powder is well-suited for hunting and target shooting. The versatility of Accurate 2520 and its easy-to-find data make it a solid choice. This powder is a strong contender in the ongoing search for the best powder for reloading 308.
Comparing the Powders
To help visualize the differences, consider a table summarizing the key characteristics of the powders:
Powder Name, Burn Rate, Ideal Bullet Weight Range (grains), Best Use, Temperature Stability,
IMR 4064, Medium, 150-180, Hunting, Target Shooting, Medium,
Varget, Medium, 150-180, Target Shooting, Hunting, High,
Reloder 15, Medium-Slow, 165-180, Hunting, Medium,
CFE 223, Fast, 110-168, Hunting, Medium,
Accurate 2520, Medium, 150-180, Hunting, Target Shooting, Medium
Reloading Tips and Considerations
Accurate Weighing
Precise powder weighing is absolutely essential for safe and accurate reloading. Use a calibrated scale and weigh each powder charge meticulously to ensure consistency. Consistent powder charges are critical for both accuracy and safety.
Seating Depth
Bullet seating depth can significantly impact accuracy. Experiment with different seating depths to find what works best for your rifle and bullet combination.
Primer Selection
Selecting appropriate primers is a step that can impact performance. Ensure you are using a primer that is compatible with the specific powder and bullet combination you are working with. Consult your reloading manual.
Brass Preparation
Proper brass preparation is important. This includes resizing, trimming, and chamfering the case mouths.
Importance of Safety
Safety is paramount in every stage of the reloading process.
Safety Precautions
Safety should always be the guiding principle in reloading. Never deviate from the recommendations in your reloading manual. Always start with the minimum recommended powder charge and work your way up gradually, carefully monitoring for signs of overpressure, such as flattened primers, difficult bolt extraction, or bulging cases. Never mix powders, as the results can be unpredictable and dangerous. Always wear safety glasses and other appropriate safety gear.
Conclusion
Choosing the best powder for reloading 308 ultimately depends on your specific needs and preferences. For excellent all-around performance and good temperature stability, Varget is a strong contender. If you prioritize a classic choice with a proven track record, IMR 4064 is a reliable option. Reloder 15 provides outstanding performance with heavier bullets. Hodgdon CFE 223 is a great choice for those looking to minimize copper fouling. Accurate 2520 also performs well.
The most effective method to identify the optimal powder for your rifle and load is to test different options. Always follow recommended guidelines. By considering your target shooting goals, the weight of the bullet, and the specifics of your rifle, you can select the powder that will give you the desired results. Safe and meticulous reloading will always give the best results. By experimenting and staying safe, you can master the art of reloading and produce custom ammunition that meets your precise needs.
Disclaimer
The information provided in this article is for informational purposes only and should not be considered professional advice. Reloading can be dangerous and requires a thorough understanding of safety procedures. Always consult a reloading manual and follow all safety guidelines. The author and publisher of this article are not responsible for any injuries or damages that may result from the use of this information. Reloading is a complex process, and it is your responsibility to ensure the safety and accuracy of your ammunition.
Call to Action
Reloading offers a rewarding experience. Share your experiences with reloading the .308, your favorite powders, or any questions you may have in the comments. Remember to consult reliable resources and experiment with different powders to find what best suits your needs. Stay safe, and enjoy the world of reloading!
