Is there a noticeable difference between copper and lead bullets in .45-70?

Performance Differences

When it comes to hunting with the .45-70 Government, particularly for large game such as elk, copper bullets demonstrate distinct performance differences compared to traditional lead bullets. Copper bullets are engineered to expand and lose kinetic energy at a faster rate, resulting in less penetration and reduced risk of causing over-penetration damage. This is crucial for hunting applications where minimizing collateral damage is essential.

Expansion and Penetration

Copper bullets in the .45-70 Government tend to expand significantly more than lead bullets, with a typical expansion ratio of 1.5:1 to 2:1. For instance, a 405-grain copper bullet may expand to approximately 0.7 inches in diameter, whereas a 405-grain lead bullet might only expand to around 0.3 inches. As a result, copper bullets tend to lose kinetic energy faster and penetrate less deeply, making them a more suitable choice for hunting large game.

Reloading Considerations

When reloading for the .45-70 Government, it’s essential to consider the specific design and requirements of copper bullets. These bullets often require a slightly deeper seating depth to ensure proper expansion and function. As a general rule, seat copper bullets 0.010 to 0.015 inches deeper than lead bullets to achieve optimal performance. Additionally, copper bullets may require specific powder charges to achieve the desired velocity and expansion characteristics. A well-designed load can make all the difference in achieving a clean, humane kill when hunting large game like elk.