The Winchester Model 70 is a legendary rifle, known for its accuracy and durability. Many shooters find themselves wanting to customize their Model 70s to better suit their specific needs, and one popular conversion is to the versatile 6mm GT cartridge. This guide provides an in-depth look at the process, considerations, and benefits of converting your Winchester Model 70 to 6mm GT.
Understanding the 6mm GT Cartridge
The 6mm GT (6mm General Target) is a relatively new cartridge, gaining popularity for its exceptional accuracy and long-range capabilities. It's based on the .260 Remington case, necked down to accept a 6mm (.243 caliber) bullet. This results in a cartridge with a superb ballistic coefficient, capable of reaching extreme distances with minimal wind drift and bullet drop. It's a favorite among precision shooters and long-range hunters.
- Key Features of the 6mm GT:
- High Ballistic Coefficient: Provides excellent long-range accuracy and reduced wind drift.
- Flat Trajectory: Allows for easier target acquisition at longer ranges.
- Moderate Recoil: Makes it comfortable to shoot for extended periods.
- Versatile Bullet Selection: Suitable for various bullet weights and designs, optimizing for various hunting and target shooting applications.
Why Convert Your Winchester Model 70 to 6mm GT?
Converting your Model 70 to 6mm GT offers several advantages:
- Enhanced Accuracy: The 6mm GT's inherently accurate design can unlock greater precision from your rifle.
- Extended Range: Reach targets further than you could with your original cartridge.
- Improved Ballistics: Experience a flatter trajectory and less wind drift.
- Customization: Tailor your rifle to your exact shooting style and preferences.
The Conversion Process: A Step-by-Step Guide
Converting your Winchester Model 70 to 6mm GT requires a combination of gunsmithing skills and specialized tools. It's generally not a DIY project for beginners. Professional gunsmithing is strongly recommended. The process typically involves:
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Barrel Replacement: This is the most crucial step. A new barrel chambered in 6mm GT must be fitted to your action. This requires precision machining and careful headspace adjustment. Choosing a reputable barrel manufacturer is essential for accuracy and reliability.
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Action Work (Possibly): Depending on the original caliber of your Model 70 and the specific gunsmith, some minor action work may be necessary to ensure proper feeding and extraction with the new cartridge.
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Bolt Face Recessing (Possibly): The bolt face might require recutting to properly accommodate the 6mm GT cartridge's case head dimensions.
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Magazine Modification: The existing magazine may need modification or replacement to reliably feed the 6mm GT rounds.
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Testing and Tuning: After the conversion, thorough testing and accuracy tuning are necessary to ensure optimal performance. This includes load development to find the best ammunition for your specific rifle.
Costs and Considerations
The cost of converting a Winchester Model 70 to 6mm GT can vary significantly depending on the gunsmith's labor rates, the barrel's quality, and any additional modifications needed. Expect to invest a substantial amount.
Factors influencing cost:
- Gunsmith's labor: This is usually the most significant cost.
- Barrel cost: High-quality barrels from reputable manufacturers can be expensive.
- Action work (if needed): Additional machining and fitting will increase the price.
- Magazine modifications (if needed): This adds to the overall cost.
Before undertaking the conversion, carefully consider the total cost and ensure it aligns with your budget.
Case Study: A Successful 6mm GT Conversion
A client recently converted their pre-64 Winchester Model 70 in .30-06 Springfield to 6mm GT. Using a high-quality Krieger barrel and meticulous gunsmithing, the rifle achieved sub-MOA accuracy at 100 yards. The client reported a significant improvement in long-range performance compared to the original .30-06 configuration. This highlights the potential for accuracy gains from a professional conversion.
Conclusion: The Rewards of Conversion
Converting your Winchester Model 70 to 6mm GT can significantly enhance its capabilities. However, it's a complex process that requires expertise. By carefully selecting a skilled gunsmith and understanding the costs involved, you can enjoy the superior accuracy, range, and versatility of this increasingly popular cartridge in your beloved Model 70. Remember, always prioritize safety and consult with experienced professionals for any firearm modifications.