Q. What are projectiles?
A. They correspond to the bullets in small-arm cartridges.
Q. Why are projectiles made oblong and guns rifled?
A. To prevent the projectile from tumbling, thereby securing greater penetration, and better results in accuracy of fire.
Q. What is the difference between guns and mortars?
A. Guns are long in comparison with their calibers, mortars are short in comparison with their calibers.
Q. What is meant by a built-up gun?
A. One that is composed of several cylindrical forgings separately shrunk one over the other.
Q. Why are these forgings shrunk on?
A. To give an initial compression to the steel toward the bore, such that the strength of the gun to resist the pressure of the powder-gas will be increased.