Understanding the .270 WSM Cartridge
History and Design
The .270 Winchester Short Magnum, often abbreviated as .270 WSM, has carved a significant niche in the world of long-range shooting and big game hunting. This cartridge, a modern take on the classic .270 caliber, offers exceptional ballistic performance, flat trajectories, and significant stopping power.
Ballistics and Typical Uses
Its design makes it ideal for hunting a wide variety of game, including deer, elk, and even larger North American species. The flat trajectory minimizes the need for holdover at longer ranges, and the considerable energy transfer ensures effective terminal performance.
Comparison with Other .270 Cartridges
The .270 WSM’s popularity stems from its inherent accuracy, its ability to push bullets to high velocities, and its suitability for both long-range shooting and hunting applications. Comparing the .270 WSM to other .270 caliber cartridges such as the .270 Winchester reveals a performance advantage in terms of speed and energy.
Essential Reloading Equipment and Components
Reloading Equipment
Reloading is a precise craft, and success hinges on the right equipment and components. Here’s a rundown of essential tools and materials needed for .270 WSM load data success:
Firstly, a robust reloading press is fundamental. This tool houses the dies and provides the mechanical advantage necessary to size, deprime, prime, and seat bullets into the case. There are many brands and styles available, with choices being based on budget and required features.
Quality reloading dies are essential. These dies come in sets, often including a full-length sizing die, a seating die, and sometimes a crimping die. Sizing dies reform the brass cases to the correct dimensions after firing, removing the spent primer and preparing the case for a new one. The seating die precisely positions the bullet in the case and may also crimp the case neck.
For accurate measuring, a digital scale is highly recommended. Precision is critical in reloading, and a digital scale provides far more accurate readings than mechanical alternatives. A scale of this type ensures consistent powder charges, which is fundamental to performance and safety.
A case trimmer, along with tools to chamfer and deburr the case mouths, is essential for consistent case length. Consistent case length enhances accuracy, ensures proper bullet seating, and aids in consistent crimping.
A priming tool, either hand-held or press-mounted, seats the primers into the case. Proper priming is another factor in achieving reliable ignition.
A powder measure dispenses the correct amount of powder into each case. Good powder measures help to maintain a consistent flow of powder.
Calipers are necessary to measure the overall length of the loaded rounds and other critical dimensions, ensuring that ammunition stays within safe and accurate parameters.
Case cleaning equipment, such as a tumbler or ultrasonic cleaner, is vital for removing grime and carbon buildup from fired cases. Clean cases are easier to handle and contribute to a cleaner reloading process.
Finally, always use safety glasses and other protective gear, such as gloves, at all times when reloading to protect against any hazard.
Reloading Components
When it comes to reloading components, selection is equally important:
Cases, of course, are the backbone of the ammunition. .270 WSM brass is widely available from reputable manufacturers. Good quality brass is worth investing in, as it directly influences the accuracy and longevity of the rounds.
Choosing the right primer can affect consistency and performance. Primer types include standard and magnum, and selection should align with the powder used. Consider respected brands like Federal, CCI, and Winchester.
Powder selection is where you can customize performance. Several powders have proven to be optimal for .270 WSM. For instance, powders with a slightly slower burn rate like Reloder 22, H1000, and IMR 4350 are suitable for loading the .270 WSM. Each powder offers unique characteristics affecting velocity, pressure curves, and the overall performance of the loaded round.
Bullet selection significantly impacts the trajectory, terminal performance, and accuracy. The .270 WSM excels with a variety of bullet weights, typically ranging from 130 to 150 grains. Consider bullet construction and weight based on the intended use. For target shooting, match-grade bullets offer superior accuracy. For hunting, consider the design and construction of the bullet. For instance, a bullet designed for expansion at impact, or one optimized for deep penetration. Popular bullet brands include Nosler, Sierra, and Hornady, each offering a wide array of bullet designs tailored to diverse needs.
.270 WSM Load Data: A Safe and Detailed Guide
Safety Precautions
Reloading provides the freedom to tailor ammunition to a specific rifle and shooting style. Always begin with meticulous attention to safety. Load data should be obtained from a trusted source, and should be followed exactly.
Remember, the most critical aspect of safe reloading is starting low and working your way up. It’s always recommended to start with the minimum powder charge specified in the load data and to gradually increase the charge in small increments. Never exceed the maximum load listed in the data.
When loading, be vigilant for warning signs. Excessive pressure can lead to:
- Flattened primers
- Sticky bolt lift
- Case head expansion
- Ruptured cases
These are all indications of excessive pressure, and you must stop immediately. If any of these occur, reduce the powder charge or consult a reloading expert.
Load Data Table (Example Only)
Here is a general guide. Please note, it is for informational purposes only, and you should refer to reputable sources for specific load data, such as reloading manuals or powder/bullet manufacturers.
| Bullet Weight (gr) | Bullet Type | Powder | Starting Load (gr) | Max Load (gr) | Primer | Velocity (fps) | Notes |
|---|---|---|---|---|---|---|---|
| 130 | Nosler Accubond | H4350 | 56.0 | 59.0 | WLR | 3000-3100 | Trim to 2.100″ |
| 140 | Sierra GameKing | Reloder 22 | 58.0 | 62.0 | Fed 210M | 2900-3000 | Seating Depth: .020″ off lands. |
| 150 | Hornady ELD-X | IMR 7828 | 60.0 | 64.0 | CCI 250 | 2800-2900 | Be mindful of case capacity when loading. |
| 140 | Barnes TSX | H1000 | 61.0 | 65.0 | WLR | 3050-3150 | Good for hunting |
| 150 | Berger Classic Hunter | Reloder 25 | 64.0 | 68.0 | Fed 210M | 2900-3000 | Excellent for long range |
Important: This is a SAMPLE table. *Always* consult reliable, up-to-date reloading manuals and powder manufacturers’ data. This information is provided for illustrative purposes, and you are fully responsible for your safety.
Reloading Process – Step-by-Step Guide
Case Preparation
The reloading process can be broken down into a set of well-defined steps, each critical for consistent performance.
The first step is case preparation. This involves: cleaning, sizing, trimming, and priming the cases. First, thoroughly clean the brass to remove any debris or residue. Ultrasonic cleaners, tumblers, or a combination of both can be used for this purpose. Next, inspect the cases carefully for any signs of damage, such as cracks, dents, or excessive wear. Cases should then be resized using a full-length sizing die, which brings the cases back to the correct dimensions, ensuring a proper fit in the chamber. The cases should then be trimmed to the specified length. This ensures that the cartridge dimensions are consistent, and that proper chambering and bullet seating occur. Next, chamfer and deburr the case mouths to remove any sharp edges, promoting smooth bullet seating and reducing the risk of damage to the bullet. Finally, prime the cases with the appropriate primers.
Powder Charging
Powder charging is a key part of the process. Using a powder measure for consistent dispensing is vital. The powder measure should be calibrated, and each charge should be carefully weighed on a digital scale to ensure accuracy and uniformity. A powder trickler can then be used to add or remove small amounts of powder until the desired weight is achieved.
Bullet Seating
After the cases are charged with powder, the bullets are seated. Carefully seat the bullet in the case to the specified depth, which impacts accuracy and pressure. The seating die is used to position the bullet at the desired depth.
Crimping
Crimping is not always necessary. Some loads do not require a crimp, while others may benefit. If crimping, it will depend on the bullet and its design. Crimping secures the bullet in the case and ensures consistent bullet release during firing.
Final Inspection
The final step is inspection. Once the ammunition is reloaded, inspect it thoroughly. Checking the overall cartridge length (OAL) to confirm that the rounds meet the specification for your rifle. Check for any visual defects or inconsistencies that could compromise safety or performance. Label the ammunition clearly with the load data.
Tips for Accuracy and Consistency
Achieving optimal accuracy and consistency in reloading is an ongoing process that requires attention to detail and a commitment to precision. Start with thorough case preparation. Ensuring consistent powder charges is a key element. Choosing the right bullet for your rifle and your intended purpose, is crucial. Then, the proper seating depth for the bullets to maximize accuracy is also key. Maintain good reloading practices, including regular cleaning of reloading equipment and attention to detail, will help you achieve the desired results. Regular testing, and load evaluation, in your rifle, is part of the process of perfecting your technique.
Troubleshooting
Even with careful preparation, reloading problems can occur.
Failure to feed is often caused by a poorly sized case or a burr on the case mouth.
Failure to extract may be due to a sticky case, often caused by inadequate sizing.
High pressure signs require immediate attention. Flattened primers, sticky bolt lift, or case head expansion are signs that the load is too hot. Reduce the powder charge immediately.
Inconsistent velocities can result from variable powder charges, inconsistent bullet seating, or improper case preparation.
Poor accuracy may arise from a number of issues.
Where to find help is important. Consult reloading manuals, online forums, and experienced reloaders. Your safety is paramount.
Conclusion
Reloading offers the .270 WSM shooter or hunter unparalleled control over their ammunition, leading to potential savings, improved accuracy, and ammunition tailored to specific needs. Safety is paramount. Start with careful research, adherence to established load data, and a cautious approach to the reloading process. Experimenting with various combinations of powders and bullets can lead to a load that is perfectly optimized for your rifle and your needs. Through diligent application of the knowledge and techniques described in this guide, you can master the art of .270 WSM reloading. Embrace the reloading process responsibly, with respect for the power of the cartridge and a dedication to safe practices.
