Does barrel length matter for 6.5 Gibbs hunting rifles?

Impact on Velocity

The 6.5 Gibbs cartridge is a relatively long cartridge, and its performance can be affected by the length of the barrel. A barrel length of 24 inches or more is generally considered optimal for the 6.5 Gibbs, as it allows for sufficient time for the bullet to stabilize and burn propellant. In one test, a 24-inch barrel resulted in an average velocity of 3,100 feet per second, compared to 2,900 feet per second with a 20-inch barrel. This represents a 6.9% increase in velocity.

Accuracy and Stabilization

The longer barrel also provides more time for the bullet to stabilize in flight, which can result in improved accuracy. The 6.5 Gibbs is a high-BC (ballistic coefficient) cartridge, and its accuracy is highly dependent on the stabilization of the bullet. A longer barrel can help to mitigate the effects of wind and other environmental factors on the bullet’s trajectory. In one test, a 24-inch barrel resulted in a 3-shot group size of 0.5 inches at 100 yards, compared to 1.2 inches with a 20-inch barrel.

Reloading Considerations

When reloading for a 6.5 Gibbs rifle with a longer barrel, it’s essential to consider the increased pressure and velocity. A longer barrel can result in higher pressures, particularly if the propellant is not properly optimized. To mitigate this, reloaders should use a slower-burning propellant and ensure that the case is properly sealed to prevent overpressure. Additionally, the longer barrel may require a slightly longer throat or a more aggressive throat cut to ensure proper bullet seating and alignment.