It is counterbored that's exactly what a counterbore is!
the first 1.5 inches of the rifling was worn out and your crown damaged. If left in this condition that damage would adversely affect accuracy.
With the counterbore only good rifling touches the bullet. The smooth spaces have no effect.
Counterboring is a way of making a rifle more accurate.
It's an M39. I'm sure you'll be pleased with the accuracy.
With the counterbore only good rifling touches the bullet. The smooth spaces have no effect.
Counterboring is a way of making a rifle more accurate.
It's an M39. I'm sure you'll be pleased with the accuracy.